diff --git a/docs/sphinx/source/pvsystem.rst b/docs/sphinx/source/pvsystem.rst
index 58d943ac79..25b9a1c9e6 100644
--- a/docs/sphinx/source/pvsystem.rst
+++ b/docs/sphinx/source/pvsystem.rst
@@ -97,7 +97,7 @@ default value may be overridden by specifying the `temp_ref` key in the
 
 .. ipython:: python
 
-    system.module_parameters['temp_ref'] = 0
+    system.arrays[0].module_parameters['temp_ref'] = 0
     # lower temp_ref should lead to lower DC power than calculated above
     pdc = system.pvwatts_dc(1000, 30)
     print(pdc)
@@ -124,7 +124,7 @@ passed to `PVSystem.module_parameters`:
     inverter_parameters = {'pdc0': 5000, 'eta_inv_nom': 0.96}
     system = pvsystem.PVSystem(module_parameters=module_parameters,
                                inverter_parameters=inverter_parameters)
-    print(system.module_parameters)
+    print(system.arrays[0].module_parameters)
     print(system.inverter_parameters)
 
 
@@ -142,12 +142,9 @@ provided for each array, and the arrays are provided to
     array_two = pvsystem.Array(module_parameters=module_parameters)
     system_two_arrays = pvsystem.PVSystem(arrays=[array_one, array_two],
                                           inverter_parameters=inverter_parameters)
-    print(system_two_arrays.module_parameters)
+    print([array.module_parameters for array in system_two_arrays.arrays])
     print(system_two_arrays.inverter_parameters)
 
-Note that in the case of a PV system with multiple arrays, the
-:py:class:`~pvlib.pvsystem.PVSystem` attribute `module_parameters` contains
-a tuple with the `module_parameters` for each array.
 
 The :py:class:`~pvlib.pvsystem.Array` class includes those 
 :py:class:`~pvlib.pvsystem.PVSystem` attributes that may vary from array
@@ -188,7 +185,8 @@ these parameters can be specified using the `PVSystem.surface_tilt` and
 
     # single south-facing array at 20 deg tilt
     system_one_array = pvsystem.PVSystem(surface_tilt=20, surface_azimuth=180)
-    print(system_one_array.surface_tilt, system_one_array.surface_azimuth)
+    print(system_one_array.arrays[0].surface_tilt,
+          system_one_array.arrays[0].surface_azimuth)
 
 
 In the case of a PV system with several arrays, the parameters are specified
@@ -201,8 +199,7 @@ for each array using the attributes `Array.surface_tilt` and `Array.surface_azim
     array_two = pvsystem.Array(surface_tilt=30, surface_azimuth=220)
     system = pvsystem.PVSystem(arrays=[array_one, array_two])
     system.num_arrays
-    system.surface_tilt
-    system.surface_azimuth
+    [(array.surface_tilt, array.surface_azimuth) for array in system.arrays]
 
 
 The `surface_tilt` and `surface_azimuth` attributes are used in PVSystem
@@ -218,7 +215,8 @@ and `solar_azimuth` as arguments.
 
     # single south-facing array at 20 deg tilt
     system_one_array = pvsystem.PVSystem(surface_tilt=20, surface_azimuth=180)
-    print(system_one_array.surface_tilt, system_one_array.surface_azimuth)
+    print(system_one_array.arrays[0].surface_tilt,
+          system_one_array.arrays[0].surface_azimuth)
 
     # call get_aoi with solar_zenith, solar_azimuth
     aoi = system_one_array.get_aoi(solar_zenith=30, solar_azimuth=180)
diff --git a/docs/sphinx/source/whatsnew/v0.9.0.rst b/docs/sphinx/source/whatsnew/v0.9.0.rst
index 240fad9c03..43b49a33a2 100644
--- a/docs/sphinx/source/whatsnew/v0.9.0.rst
+++ b/docs/sphinx/source/whatsnew/v0.9.0.rst
@@ -85,6 +85,22 @@ Deprecations
 * The ``eta_m`` parameter for :py:func:`~pvlib.temperature.pvsyst_cell` is
   replaced by parameter ``module_efficiency``. (:issue:`1188`, :pull:`1218`)
 
+* The following attributes of :py:class:`pvlib.pvsystem.PVSystem` and
+  :py:class:`pvlib.tracking.SingleAxisTracker` have been deprecated in
+  favor of the corresponding :py:class:`pvlib.pvsystem.Array` attributes:
+
+  * ``PVSystem.albedo``
+  * ``PVSystem.module``
+  * ``PVSystem.module_parameters``
+  * ``PVSystem.module_type``
+  * ``PVSystem.modules_per_string``
+  * ``PVSystem.racking_model``
+  * ``PVSystem.strings_per_inverter``
+  * ``PVSystem.surface_tilt``
+  * ``PVSystem.surface_azimuth``
+  * ``PVSystem.temperature_model_parameters``
+
+
 Enhancements
 ~~~~~~~~~~~~
 * Add :func:`~pvlib.iotools.read_bsrn` for reading BSRN solar radiation data
diff --git a/pvlib/modelchain.py b/pvlib/modelchain.py
index 8cc49153fa..eb0db817fd 100644
--- a/pvlib/modelchain.py
+++ b/pvlib/modelchain.py
@@ -408,29 +408,32 @@ class ModelChain:
         Passed to location.get_airmass.
 
     dc_model: None, str, or function, default None
-        If None, the model will be inferred from the contents of
-        system.module_parameters. Valid strings are 'sapm',
-        'desoto', 'cec', 'pvsyst', 'pvwatts'. The ModelChain instance will
-        be passed as the first argument to a user-defined function.
+        If None, the model will be inferred from the parameters that
+        are common to all of system.arrays[i].module_parameters.
+        Valid strings are 'sapm', 'desoto', 'cec', 'pvsyst', 'pvwatts'.
+        The ModelChain instance will be passed as the first argument
+        to a user-defined function.
 
     ac_model: None, str, or function, default None
-        If None, the model will be inferred from the contents of
-        system.inverter_parameters and system.module_parameters. Valid
-        strings are 'sandia', 'adr', 'pvwatts'. The
+        If None, the model will be inferred from the parameters that
+        are common to all of system.inverter_parameters.
+        Valid strings are 'sandia', 'adr', 'pvwatts'. The
         ModelChain instance will be passed as the first argument to a
         user-defined function.
 
     aoi_model: None, str, or function, default None
-        If None, the model will be inferred from the contents of
-        system.module_parameters. Valid strings are 'physical',
-        'ashrae', 'sapm', 'martin_ruiz', 'no_loss'. The ModelChain instance
-        will be passed as the first argument to a user-defined function.
+        If None, the model will be inferred from the parameters that
+        are common to all of system.arrays[i].module_parameters.
+        Valid strings are 'physical', 'ashrae', 'sapm', 'martin_ruiz',
+        'no_loss'. The ModelChain instance will be passed as the
+        first argument to a user-defined function.
 
     spectral_model: None, str, or function, default None
-        If None, the model will be inferred from the contents of
-        system.module_parameters. Valid strings are 'sapm',
-        'first_solar', 'no_loss'. The ModelChain instance will be passed
-        as the first argument to a user-defined function.
+        If None, the model will be inferred from the parameters that
+        are common to all of system.arrays[i].module_parameters.
+        Valid strings are 'sapm', 'first_solar', 'no_loss'.
+        The ModelChain instance will be passed as the first argument to
+        a user-defined function.
 
     temperature_model: None, str or function, default None
         Valid strings are: 'sapm', 'pvsyst', 'faiman', 'fuentes', 'noct_sam'.
@@ -691,9 +694,10 @@ def dc_model(self, model):
             model = model.lower()
             if model in _DC_MODEL_PARAMS.keys():
                 # validate module parameters
+                module_parameters = tuple(
+                    array.module_parameters for array in self.system.arrays)
                 missing_params = (
-                    _DC_MODEL_PARAMS[model] -
-                    _common_keys(self.system.module_parameters))
+                    _DC_MODEL_PARAMS[model] - _common_keys(module_parameters))
                 if missing_params:  # some parameters are not in module.keys()
                     raise ValueError(model + ' selected for the DC model but '
                                      'one or more Arrays are missing '
@@ -716,7 +720,8 @@ def dc_model(self, model):
 
     def infer_dc_model(self):
         """Infer DC power model from Array module parameters."""
-        params = _common_keys(self.system.module_parameters)
+        params = _common_keys(
+            tuple(array.module_parameters for array in self.system.arrays))
         if {'A0', 'A1', 'C7'} <= params:
             return self.sapm, 'sapm'
         elif {'a_ref', 'I_L_ref', 'I_o_ref', 'R_sh_ref', 'R_s',
@@ -730,10 +735,11 @@ def infer_dc_model(self):
         elif {'pdc0', 'gamma_pdc'} <= params:
             return self.pvwatts_dc, 'pvwatts'
         else:
-            raise ValueError('could not infer DC model from '
-                             'system.module_parameters. Check '
-                             'system.module_parameters or explicitly '
-                             'set the model with the dc_model kwarg.')
+            raise ValueError(
+                'Could not infer DC model from the module_parameters '
+                'attributes of system.arrays. Check the module_parameters '
+                'attributes or explicitly set the model with the dc_model '
+                'keyword argument.')
 
     def sapm(self):
         dc = self.system.sapm(self.results.effective_irradiance,
@@ -782,7 +788,7 @@ def pvwatts_dc(self):
         """Calculate DC power using the PVWatts model.
 
         Results are stored in ModelChain.results.dc. DC power is computed
-        from PVSystem.module_parameters['pdc0'] and then scaled by
+        from PVSystem.arrays[i].module_parameters['pdc0'] and then scaled by
         PVSystem.modules_per_string and PVSystem.strings_per_inverter.
 
         Returns
@@ -891,7 +897,9 @@ def aoi_model(self, model):
             self._aoi_model = partial(model, self)
 
     def infer_aoi_model(self):
-        params = _common_keys(self.system.module_parameters)
+        module_parameters = tuple(
+            array.module_parameters for array in self.system.arrays)
+        params = _common_keys(module_parameters)
         if {'K', 'L', 'n'} <= params:
             return self.physical_aoi_loss
         elif {'B5', 'B4', 'B3', 'B2', 'B1', 'B0'} <= params:
@@ -902,8 +910,8 @@ def infer_aoi_model(self):
             return self.martin_ruiz_aoi_loss
         else:
             raise ValueError('could not infer AOI model from '
-                             'system.module_parameters. Check that the '
-                             'module_parameters for all Arrays in '
+                             'system.arrays[i].module_parameters. Check that '
+                             'the module_parameters for all Arrays in '
                              'system.arrays contain parameters for '
                              'the physical, aoi, ashrae or martin_ruiz model; '
                              'explicitly set the model with the aoi_model '
@@ -966,7 +974,9 @@ def spectral_model(self, model):
 
     def infer_spectral_model(self):
         """Infer spectral model from system attributes."""
-        params = _common_keys(self.system.module_parameters)
+        module_parameters = tuple(
+            array.module_parameters for array in self.system.arrays)
+        params = _common_keys(module_parameters)
         if {'A4', 'A3', 'A2', 'A1', 'A0'} <= params:
             return self.sapm_spectral_loss
         elif ((('Technology' in params or
@@ -976,8 +986,8 @@ def infer_spectral_model(self):
             return self.first_solar_spectral_loss
         else:
             raise ValueError('could not infer spectral model from '
-                             'system.module_parameters. Check that the '
-                             'module_parameters for all Arrays in '
+                             'system.arrays[i].module_parameters. Check that '
+                             'the module_parameters for all Arrays in '
                              'system.arrays contain valid '
                              'first_solar_spectral_coefficients, a valid '
                              'Material or Technology value, or set '
@@ -1028,20 +1038,24 @@ def temperature_model(self, model):
             # check system.temperature_model_parameters for consistency
             name_from_params = self.infer_temperature_model().__name__
             if self._temperature_model.__name__ != name_from_params:
+                common_params = _common_keys(tuple(
+                    array.temperature_model_parameters
+                    for array in self.system.arrays))
                 raise ValueError(
                     f'Temperature model {self._temperature_model.__name__} is '
                     f'inconsistent with PVSystem temperature model '
                     f'parameters. All Arrays in system.arrays must have '
                     f'consistent parameters. Common temperature model '
-                    f'parameters: '
-                    f'{_common_keys(self.system.temperature_model_parameters)}'
+                    f'parameters: {common_params}'
                 )
         else:
             self._temperature_model = partial(model, self)
 
     def infer_temperature_model(self):
         """Infer temperature model from system attributes."""
-        params = _common_keys(self.system.temperature_model_parameters)
+        temperature_model_parameters = tuple(
+            array.temperature_model_parameters for array in self.system.arrays)
+        params = _common_keys(temperature_model_parameters)
         # remove or statement in v0.9
         if {'a', 'b', 'deltaT'} <= params or (
                 not params and self.system.racking_model is None
@@ -1195,7 +1209,7 @@ def _eff_irrad(module_parameters, total_irrad, spect_mod, aoi_mod):
                     self.results.spectral_modifier, self.results.aoi_modifier))
         else:
             self.results.effective_irradiance = _eff_irrad(
-                self.system.module_parameters,
+                self.system.arrays[0].module_parameters,
                 self.results.total_irrad,
                 self.results.spectral_modifier,
                 self.results.aoi_modifier
@@ -1629,7 +1643,7 @@ def _prepare_temperature_single_array(self, data, poa):
         self.results.cell_temperature = self._get_cell_temperature(
             data,
             poa,
-            self.system.temperature_model_parameters
+            self.system.arrays[0].temperature_model_parameters
         )
         if self.results.cell_temperature is None:
             self.temperature_model()
diff --git a/pvlib/pvsystem.py b/pvlib/pvsystem.py
index 7623cc009f..43b856b903 100644
--- a/pvlib/pvsystem.py
+++ b/pvlib/pvsystem.py
@@ -64,6 +64,37 @@ def f(*args, **kwargs):
     return f
 
 
+def _check_deprecated_passthrough(func):
+    """
+    Decorator to warn or error when getting and setting the "pass-through"
+    PVSystem properties that have been moved to Array.  Emits a warning for
+    PVSystems with only one Array and raises an error for PVSystems with
+    more than one Array.
+    """
+
+    @functools.wraps(func)
+    def wrapper(self, *args, **kwargs):
+        pvsystem_attr = func.__name__
+        class_name = self.__class__.__name__  # PVSystem or SingleAxisTracker
+        overrides = {  # some Array attrs aren't the same as PVSystem
+            'strings_per_inverter': 'strings',
+        }
+        array_attr = overrides.get(pvsystem_attr, pvsystem_attr)
+        alternative = f'{class_name}.arrays[i].{array_attr}'
+
+        if len(self.arrays) > 1:
+            raise AttributeError(
+                f'{class_name}.{pvsystem_attr} not supported for multi-array '
+                f'systems. Set {array_attr} for each Array in '
+                f'{class_name}.arrays instead.')
+
+        wrapped = deprecated('0.9', alternative=alternative, removal='0.10',
+                             name=f"{class_name}.{pvsystem_attr}")(func)
+        return wrapped(self, *args, **kwargs)
+
+    return wrapper
+
+
 # not sure if this belongs in the pvsystem module.
 # maybe something more like core.py? It may eventually grow to
 # import a lot more functionality from other modules.
@@ -1083,75 +1114,125 @@ def dc_ohms_from_percent(self):
 
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def module_parameters(self):
         return tuple(array.module_parameters for array in self.arrays)
 
+    @module_parameters.setter
+    @_check_deprecated_passthrough
+    def module_parameters(self, value):
+        for array in self.arrays:
+            array.module_parameters = value
+
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def module(self):
         return tuple(array.module for array in self.arrays)
 
+    @module.setter
+    @_check_deprecated_passthrough
+    def module(self, value):
+        for array in self.arrays:
+            array.module = value
+
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def module_type(self):
         return tuple(array.module_type for array in self.arrays)
 
+    @module_type.setter
+    @_check_deprecated_passthrough
+    def module_type(self, value):
+        for array in self.arrays:
+            array.module_type = value
+
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def temperature_model_parameters(self):
         return tuple(array.temperature_model_parameters
                      for array in self.arrays)
 
     @temperature_model_parameters.setter
+    @_check_deprecated_passthrough
     def temperature_model_parameters(self, value):
         for array in self.arrays:
             array.temperature_model_parameters = value
 
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def surface_tilt(self):
         return tuple(array.surface_tilt for array in self.arrays)
 
     @surface_tilt.setter
+    @_check_deprecated_passthrough
     def surface_tilt(self, value):
         for array in self.arrays:
             array.surface_tilt = value
 
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def surface_azimuth(self):
         return tuple(array.surface_azimuth for array in self.arrays)
 
     @surface_azimuth.setter
+    @_check_deprecated_passthrough
     def surface_azimuth(self, value):
         for array in self.arrays:
             array.surface_azimuth = value
 
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def albedo(self):
         return tuple(array.albedo for array in self.arrays)
 
+    @albedo.setter
+    @_check_deprecated_passthrough
+    def albedo(self, value):
+        for array in self.arrays:
+            array.albedo = value
+
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def racking_model(self):
         return tuple(array.racking_model for array in self.arrays)
 
     @racking_model.setter
+    @_check_deprecated_passthrough
     def racking_model(self, value):
         for array in self.arrays:
             array.racking_model = value
 
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def modules_per_string(self):
         return tuple(array.modules_per_string for array in self.arrays)
 
+    @modules_per_string.setter
+    @_check_deprecated_passthrough
+    def modules_per_string(self, value):
+        for array in self.arrays:
+            array.modules_per_string = value
+
     @property
     @_unwrap_single_value
+    @_check_deprecated_passthrough
     def strings_per_inverter(self):
         return tuple(array.strings for array in self.arrays)
 
+    @strings_per_inverter.setter
+    @_check_deprecated_passthrough
+    def strings_per_inverter(self, value):
+        for array in self.arrays:
+            array.strings = value
+
     @property
     def num_arrays(self):
         """The number of Arrays in the system."""
diff --git a/pvlib/tests/test_modelchain.py b/pvlib/tests/test_modelchain.py
index 88b2104c99..4d2edbccae 100644
--- a/pvlib/tests/test_modelchain.py
+++ b/pvlib/tests/test_modelchain.py
@@ -658,8 +658,8 @@ def test_run_model_with_weather_pvsyst_temp(sapm_dc_snl_ac_system, location,
     # test with pvsyst cell temperature model
     weather['wind_speed'] = 5
     weather['temp_air'] = 10
-    sapm_dc_snl_ac_system.racking_model = 'freestanding'
-    sapm_dc_snl_ac_system.temperature_model_parameters = \
+    sapm_dc_snl_ac_system.arrays[0].racking_model = 'freestanding'
+    sapm_dc_snl_ac_system.arrays[0].temperature_model_parameters = \
         temperature._temperature_model_params('pvsyst', 'freestanding')
     mc = ModelChain(sapm_dc_snl_ac_system, location)
     mc.temperature_model = 'pvsyst'
@@ -677,7 +677,7 @@ def test_run_model_with_weather_faiman_temp(sapm_dc_snl_ac_system, location,
     # test with faiman cell temperature model
     weather['wind_speed'] = 5
     weather['temp_air'] = 10
-    sapm_dc_snl_ac_system.temperature_model_parameters = {
+    sapm_dc_snl_ac_system.arrays[0].temperature_model_parameters = {
         'u0': 25.0, 'u1': 6.84
     }
     mc = ModelChain(sapm_dc_snl_ac_system, location)
@@ -695,7 +695,7 @@ def test_run_model_with_weather_fuentes_temp(sapm_dc_snl_ac_system, location,
                                              weather, mocker):
     weather['wind_speed'] = 5
     weather['temp_air'] = 10
-    sapm_dc_snl_ac_system.temperature_model_parameters = {
+    sapm_dc_snl_ac_system.arrays[0].temperature_model_parameters = {
         'noct_installed': 45
     }
     mc = ModelChain(sapm_dc_snl_ac_system, location)
@@ -731,9 +731,9 @@ def test_run_model_with_weather_noct_sam_temp(sapm_dc_snl_ac_system, location,
 
 def test_run_model_tracker(sapm_dc_snl_ac_system, location, weather, mocker):
     system = SingleAxisTracker(
-        module_parameters=sapm_dc_snl_ac_system.module_parameters,
+        module_parameters=sapm_dc_snl_ac_system.arrays[0].module_parameters,
         temperature_model_parameters=(
-            sapm_dc_snl_ac_system.temperature_model_parameters
+            sapm_dc_snl_ac_system.arrays[0].temperature_model_parameters
         ),
         inverter_parameters=sapm_dc_snl_ac_system.inverter_parameters)
     mocker.spy(system, 'singleaxis')
@@ -752,9 +752,9 @@ def test_run_model_tracker(sapm_dc_snl_ac_system, location, weather, mocker):
 def test_run_model_tracker_list(
         sapm_dc_snl_ac_system, location, weather, mocker):
     system = SingleAxisTracker(
-        module_parameters=sapm_dc_snl_ac_system.module_parameters,
+        module_parameters=sapm_dc_snl_ac_system.arrays[0].module_parameters,
         temperature_model_parameters=(
-            sapm_dc_snl_ac_system.temperature_model_parameters
+            sapm_dc_snl_ac_system.arrays[0].temperature_model_parameters
         ),
         inverter_parameters=sapm_dc_snl_ac_system.inverter_parameters)
     mocker.spy(system, 'singleaxis')
@@ -952,8 +952,8 @@ def test_temperature_models_arrays_multi_weather(
         temp_params, temp_model,
         sapm_dc_snl_ac_system_same_arrays,
         location, weather, total_irrad):
-    sapm_dc_snl_ac_system_same_arrays.temperature_model_parameters = \
-        temp_params
+    for array in sapm_dc_snl_ac_system_same_arrays.arrays:
+        array.temperature_model_parameters = temp_params
     # set air temp so it does not default to the same value for both arrays
     weather['temp_air'] = 25
     weather_one = weather
@@ -1024,9 +1024,9 @@ def test_run_model_from_poa_arrays_solar_position_weather(
 def test_run_model_from_poa_tracking(sapm_dc_snl_ac_system, location,
                                      total_irrad):
     system = SingleAxisTracker(
-        module_parameters=sapm_dc_snl_ac_system.module_parameters,
+        module_parameters=sapm_dc_snl_ac_system.arrays[0].module_parameters,
         temperature_model_parameters=(
-            sapm_dc_snl_ac_system.temperature_model_parameters
+            sapm_dc_snl_ac_system.arrays[0].temperature_model_parameters
         ),
         inverter_parameters=sapm_dc_snl_ac_system.inverter_parameters)
     mc = ModelChain(system, location, aoi_model='no_loss',
@@ -1243,11 +1243,13 @@ def test_infer_dc_model(sapm_dc_snl_ac_system, cec_dc_snl_ac_system,
     temp_model_params = {'sapm': {'a': -3.40641, 'b': -0.0842075, 'deltaT': 3},
                          'pvsyst': {'u_c': 29.0, 'u_v': 0}}
     system = dc_systems[dc_model]
-    system.temperature_model_parameters = temp_model_params[
-        temp_model_function[dc_model]]
+    for array in system.arrays:
+        array.temperature_model_parameters = temp_model_params[
+            temp_model_function[dc_model]]
     # remove Adjust from model parameters for desoto, singlediode
     if dc_model in ['desoto', 'singlediode']:
-        system.module_parameters.pop('Adjust')
+        for array in system.arrays:
+            array.module_parameters.pop('Adjust')
     m = mocker.spy(pvsystem, dc_model_function[dc_model])
     mc = ModelChain(system, location,
                     aoi_model='no_loss', spectral_model='no_loss',
@@ -1257,6 +1259,15 @@ def test_infer_dc_model(sapm_dc_snl_ac_system, cec_dc_snl_ac_system,
     assert isinstance(mc.results.dc, (pd.Series, pd.DataFrame))
 
 
+def test_infer_dc_model_incomplete(multi_array_sapm_dc_snl_ac_system,
+                                   location):
+    match = 'Could not infer DC model from the module_parameters attributes '
+    system = multi_array_sapm_dc_snl_ac_system['two_array_system']
+    system.arrays[0].module_parameters.pop('A0')
+    with pytest.raises(ValueError, match=match):
+        ModelChain(system, location)
+
+
 @pytest.mark.parametrize('dc_model', ['cec', 'desoto', 'pvsyst'])
 def test_singlediode_dc_arrays(location, dc_model,
                                cec_dc_snl_ac_arrays,
@@ -1272,10 +1283,11 @@ def test_singlediode_dc_arrays(location, dc_model,
                          'pvsyst': temp_pvsyst}
     temp_model = {'cec': 'sapm', 'desoto': 'sapm', 'pvsyst': 'pvsyst'}
     system = systems[dc_model]
-    system.temperature_model_parameters = temp_model_params[dc_model]
+    for array in system.arrays:
+        array.temperature_model_parameters = temp_model_params[dc_model]
     if dc_model == 'desoto':
-        for module_parameters in system.module_parameters:
-            module_parameters.pop('Adjust')
+        for array in system.arrays:
+            array.module_parameters.pop('Adjust')
     mc = ModelChain(system, location,
                     aoi_model='no_loss', spectral_model='no_loss',
                     temperature_model=temp_model[dc_model])
@@ -1320,7 +1332,7 @@ def test_infer_temp_model(location, sapm_dc_snl_ac_system,
 
 
 def test_infer_temp_model_invalid(location, sapm_dc_snl_ac_system):
-    sapm_dc_snl_ac_system.temperature_model_parameters.pop('a')
+    sapm_dc_snl_ac_system.arrays[0].temperature_model_parameters.pop('a')
     with pytest.raises(ValueError):
         ModelChain(sapm_dc_snl_ac_system, location,
                    aoi_model='physical', spectral_model='no_loss')
@@ -1498,7 +1510,7 @@ def test_aoi_model_user_func(sapm_dc_snl_ac_system, location, weather, mocker):
 ])
 def test_infer_aoi_model(location, system_no_aoi, aoi_model):
     for k in iam._IAM_MODEL_PARAMS[aoi_model]:
-        system_no_aoi.module_parameters.update({k: 1.0})
+        system_no_aoi.arrays[0].module_parameters.update({k: 1.0})
     mc = ModelChain(system_no_aoi, location, spectral_model='no_loss')
     assert isinstance(mc, ModelChain)
 
@@ -1703,19 +1715,24 @@ def test_invalid_dc_model_params(sapm_dc_snl_ac_system, cec_dc_snl_ac_system,
     kwargs = {'dc_model': 'sapm', 'ac_model': 'sandia',
               'aoi_model': 'no_loss', 'spectral_model': 'no_loss',
               'temperature_model': 'sapm', 'losses_model': 'no_loss'}
-    sapm_dc_snl_ac_system.module_parameters.pop('A0')  # remove a parameter
+    for array in sapm_dc_snl_ac_system.arrays:
+        array.module_parameters.pop('A0')  # remove a parameter
     with pytest.raises(ValueError):
         ModelChain(sapm_dc_snl_ac_system, location, **kwargs)
 
     kwargs['dc_model'] = 'singlediode'
-    cec_dc_snl_ac_system.module_parameters.pop('a_ref')  # remove a parameter
+    for array in cec_dc_snl_ac_system.arrays:
+        array.module_parameters.pop('a_ref')  # remove a parameter
     with pytest.raises(ValueError):
         ModelChain(cec_dc_snl_ac_system, location, **kwargs)
 
     kwargs['dc_model'] = 'pvwatts'
     kwargs['ac_model'] = 'pvwatts'
-    pvwatts_dc_pvwatts_ac_system.module_parameters.pop('pdc0')
-    with pytest.raises(ValueError):
+    for array in pvwatts_dc_pvwatts_ac_system.arrays:
+        array.module_parameters.pop('pdc0')
+
+    match = 'one or more Arrays are missing one or more required parameters'
+    with pytest.raises(ValueError, match=match):
         ModelChain(pvwatts_dc_pvwatts_ac_system, location, **kwargs)
 
 
diff --git a/pvlib/tests/test_pvsystem.py b/pvlib/tests/test_pvsystem.py
index 19bfc40e25..d0abdefd4b 100644
--- a/pvlib/tests/test_pvsystem.py
+++ b/pvlib/tests/test_pvsystem.py
@@ -1581,7 +1581,9 @@ def test_PVSystem_get_ac_invalid(cec_inverter_parameters):
 def test_PVSystem_creation():
     pv_system = pvsystem.PVSystem(module='blah', inverter='blarg')
     # ensure that parameter attributes are dict-like. GH 294
-    pv_system.module_parameters['pdc0'] = 1
+    with pytest.warns(pvlibDeprecationWarning):
+        pv_system.module_parameters['pdc0'] = 1
+
     pv_system.inverter_parameters['Paco'] = 1
 
 
@@ -1589,9 +1591,6 @@ def test_PVSystem_multiple_array_creation():
     array_one = pvsystem.Array(surface_tilt=32)
     array_two = pvsystem.Array(surface_tilt=15, module_parameters={'pdc0': 1})
     pv_system = pvsystem.PVSystem(arrays=[array_one, array_two])
-    assert pv_system.surface_tilt == (32, 15)
-    assert pv_system.surface_azimuth == (180, 180)
-    assert pv_system.module_parameters == ({}, {'pdc0': 1})
     assert pv_system.arrays == (array_one, array_two)
     with pytest.raises(TypeError):
         pvsystem.PVSystem(arrays=array_one)
@@ -1770,41 +1769,60 @@ def test_PVSystem_multi_array_get_irradiance_multi_irrad():
 
 def test_PVSystem_change_surface_azimuth():
     system = pvsystem.PVSystem(surface_azimuth=180)
-    assert system.surface_azimuth == 180
-    system.surface_azimuth = 90
-    assert system.surface_azimuth == 90
+    with pytest.warns(pvlibDeprecationWarning):
+        assert system.surface_azimuth == 180
+    with pytest.warns(pvlibDeprecationWarning):
+        system.surface_azimuth = 90
+    with pytest.warns(pvlibDeprecationWarning):
+        assert system.surface_azimuth == 90
 
 
-def test_PVSystem_get_albedo(two_array_system):
+def test_PVSystem_get_albedo():
     system = pvsystem.PVSystem(
         arrays=[pvsystem.Array(albedo=0.5)]
     )
-    assert system.albedo == 0.5
-    assert two_array_system.albedo == (0.25, 0.25)
+    with pytest.warns(pvlibDeprecationWarning):
+        assert system.albedo == 0.5
 
 
 def test_PVSystem_modules_per_string():
-    system = pvsystem.PVSystem(
-        arrays=[pvsystem.Array(modules_per_string=1),
-                pvsystem.Array(modules_per_string=2)]
-    )
-    assert system.modules_per_string == (1, 2)
     system = pvsystem.PVSystem(
         arrays=[pvsystem.Array(modules_per_string=5)]
     )
-    assert system.modules_per_string == 5
+    with pytest.warns(pvlibDeprecationWarning):
+        assert system.modules_per_string == 5
 
 
 def test_PVSystem_strings_per_inverter():
-    system = pvsystem.PVSystem(
-        arrays=[pvsystem.Array(strings=2),
-                pvsystem.Array(strings=1)]
-    )
-    assert system.strings_per_inverter == (2, 1)
     system = pvsystem.PVSystem(
         arrays=[pvsystem.Array(strings=5)]
     )
-    assert system.strings_per_inverter == 5
+    with pytest.warns(pvlibDeprecationWarning):
+        assert system.strings_per_inverter == 5
+
+
+@fail_on_pvlib_version('0.10')
+@pytest.mark.parametrize('attr', ['module_parameters', 'module', 'module_type',
+                                  'temperature_model_parameters', 'albedo',
+                                  'surface_tilt', 'surface_azimuth',
+                                  'racking_model', 'modules_per_string',
+                                  'strings_per_inverter'])
+def test_PVSystem_multi_array_attributes(attr):
+    array_one = pvsystem.Array()
+    array_two = pvsystem.Array()
+    system = pvsystem.PVSystem(arrays=[array_one, array_two])
+    with pytest.raises(AttributeError):
+        getattr(system, attr)
+
+    with pytest.raises(AttributeError):
+        setattr(system, attr, 'dummy')
+
+    system = pvsystem.PVSystem()
+    with pytest.warns(pvlibDeprecationWarning):
+        getattr(system, attr)
+
+    with pytest.warns(pvlibDeprecationWarning):
+        setattr(system, attr, 'dummy')
 
 
 def test_PVSystem___repr__():
@@ -1959,7 +1977,8 @@ def test_PVSystem_pvwatts_dc(pvwatts_system_defaults, mocker):
     expected = 90
     out = pvwatts_system_defaults.pvwatts_dc(irrad, temp_cell)
     pvsystem.pvwatts_dc.assert_called_once_with(
-        irrad, temp_cell, **pvwatts_system_defaults.module_parameters)
+        irrad, temp_cell,
+        **pvwatts_system_defaults.arrays[0].module_parameters)
     assert_allclose(expected, out, atol=10)
 
 
@@ -1970,7 +1989,7 @@ def test_PVSystem_pvwatts_dc_kwargs(pvwatts_system_kwargs, mocker):
     expected = 90
     out = pvwatts_system_kwargs.pvwatts_dc(irrad, temp_cell)
     pvsystem.pvwatts_dc.assert_called_once_with(
-        irrad, temp_cell, **pvwatts_system_kwargs.module_parameters)
+        irrad, temp_cell, **pvwatts_system_kwargs.arrays[0].module_parameters)
     assert_allclose(expected, out, atol=10)
 
 
diff --git a/pvlib/tests/test_tracking.py b/pvlib/tests/test_tracking.py
index b6ae20ca67..ee4a9b8d12 100644
--- a/pvlib/tests/test_tracking.py
+++ b/pvlib/tests/test_tracking.py
@@ -297,7 +297,7 @@ def test_SingleAxisTracker_creation():
 
     assert system.max_angle == 45
     assert system.gcr == .25
-    assert system.module == 'blah'
+    assert system.arrays[0].module == 'blah'
     assert system.inverter == 'blarg'
 
 
@@ -309,7 +309,7 @@ def test_SingleAxisTracker_one_array_only():
             surface_azimuth=None
         )]
     )
-    assert system.module == 'foo'
+    assert system.arrays[0].module == 'foo'
     with pytest.raises(ValueError,
                        match="SingleAxisTracker does not support "
                              r"multiple arrays\."):
diff --git a/pvlib/tracking.py b/pvlib/tracking.py
index 8dd9e43461..9aa4919198 100644
--- a/pvlib/tracking.py
+++ b/pvlib/tracking.py
@@ -239,7 +239,7 @@ def get_irradiance(self, surface_tilt, surface_azimuth,
                 dni_extra=dni_extra,
                 airmass=airmass,
                 model=model,
-                albedo=self.albedo,
+                albedo=self.arrays[0].albedo,
                 **kwargs)
             for array, dni, ghi, dhi in zip(
                 self.arrays, dni, ghi, dhi