diff --git a/lib/signer.js b/lib/signer.js
index aa2ef3a..0e281d1 100644
--- a/lib/signer.js
+++ b/lib/signer.js
@@ -234,7 +234,9 @@ RequestSigner.prototype.sign = function (cb) {
       cb(e);
       return;
     }
-    alg = (this.rs_alg[0] || this.rs_key.type) + '-' + sigObj.hashAlgorithm;
+    alg = sigObj.hideAlgorithm ?
+        'hs2019' :
+        (this.rs_alg[0] || this.rs_key.type) + '-' + sigObj.hashAlgorithm;
     var signature = sigObj.toString();
     authz = FormatAuthz('Signature ', {
       keyId: this.rs_keyId,
@@ -310,6 +312,9 @@ module.exports = {
    *                              pass to sshpk to parse the privateKey.
    *                              This doesn't do anything if algorithm is
    *                              HMAC.
+   *                   - {Boolean} hideAlgorithm optional; defaults to 'false'.
+   *                               if true, hides algorithm by writing "hs2019"
+   *                               to signature.
    * @return {Boolean} true if Authorization (and optionally Date) were added.
    * @throws {TypeError} on bad parameter types (input).
    * @throws {InvalidAlgorithmError} if algorithm was bad or incompatible with
@@ -328,6 +333,7 @@ module.exports = {
     assert.optionalString(options.httpVersion, 'options.httpVersion');
     assert.optionalNumber(options.expiresIn, 'options.expiresIn');
     assert.optionalString(options.keyPassphrase, 'options.keyPassphrase');
+    assert.optionalBool(options.hideAlgorithm, 'options.hideAlgorithm');
 
     if (!request.getHeader('Date'))
       request.setHeader('Date', jsprim.rfc1123(new Date()));
@@ -372,7 +378,9 @@ module.exports = {
         alg[1] = key.defaultHashAlgorithm();
       }
 
-      options.algorithm = alg[0] + '-' + alg[1];
+      options.algorithm = options.hideAlgorithm ?
+          'hs2019' :
+          alg[0] + '-' + alg[1];
     }
 
     var params = {
diff --git a/lib/utils.js b/lib/utils.js
index 65a4b8f..fb10440 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -35,9 +35,24 @@ function InvalidAlgorithmError(message) {
 }
 util.inherits(InvalidAlgorithmError, HttpSignatureError);
 
-function validateAlgorithm(algorithm) {
+/**
+ * @param algorithm {String} the algorithm of the signature
+ * @param publicKeyType {String?} fallback algorithm (public key type) for
+ *                                hs2019
+ * @returns {[string, string]}
+ */
+function validateAlgorithm(algorithm, publicKeyType) {
+  assert.string(algorithm, 'algorithm');
+  assert.optionalString(publicKeyType, 'publicKeyType');
+
   var alg = algorithm.toLowerCase().split('-');
 
+  if (alg[0] === 'hs2019') {
+    return publicKeyType !== undefined ?
+        validateAlgorithm(publicKeyType + '-sha512') :
+        ['hs2019', 'sha512'];
+  }
+
   if (alg.length !== 2) {
     throw (new InvalidAlgorithmError(alg[0].toUpperCase() + ' is not a ' +
       'valid algorithm'));
diff --git a/lib/verify.js b/lib/verify.js
index 4dba400..362464f 100644
--- a/lib/verify.js
+++ b/lib/verify.js
@@ -30,9 +30,9 @@ module.exports = {
       pubkey = sshpk.parseKey(pubkey);
     assert.ok(sshpk.Key.isKey(pubkey, [1, 1]), 'pubkey must be a sshpk.Key');
 
-    var alg = validateAlgorithm(parsedSignature.algorithm);
+    var alg = validateAlgorithm(parsedSignature.algorithm, pubkey.type);
     if (alg[0] === 'hmac' || alg[0] !== pubkey.type)
-      return (false);
+      return false;
 
     var v = pubkey.createVerify(alg[1]);
     v.update(parsedSignature.signingString);
diff --git a/test/signer.test.js b/test/signer.test.js
index 802e422..f5d464a 100644
--- a/test/signer.test.js
+++ b/test/signer.test.js
@@ -244,6 +244,28 @@ test('signing with unspecified algorithm', function(t) {
   req.end();
 });
 
+test('hide algorithm (unspecified algorithm)', function(t) {
+  var req = http.request(httpOptions, function(res) {
+    t.end();
+  });
+  var opts = {
+    keyId: 'unit',
+    key: rsaPrivate,
+    headers: ['date', '(algorithm)'],
+    hideAlgorithm: true,
+  };
+
+  req._stringToSign = null;
+  t.ok(httpSignature.sign(req, opts));
+  t.ok(req.getHeader('Authorization'));
+  t.strictEqual(typeof (opts.algorithm), 'string');
+  t.strictEqual(opts.algorithm, 'hs2019');
+  t.strictEqual(typeof (req._stringToSign), 'string');
+  t.ok(req._stringToSign.match(/^date: [^\n]*\n\(algorithm\): [^\n]*$/));
+  console.log('> ' + req.getHeader('Authorization'));
+  req.end();
+});
+
 test('signing opaque param', function(t) {
   var req = http.request(httpOptions, function(res) {
     t.end();
diff --git a/test/verify.test.js b/test/verify.test.js
index 19dd062..16c0e0b 100644
--- a/test/verify.test.js
+++ b/test/verify.test.js
@@ -292,6 +292,123 @@ test('valid ecdsa', function(t) {
 });
 
 
+test('invalid hs2019', function(t) {
+  server.tester = function(req, res) {
+    var parsed = httpSignature.parseRequest(req);
+    t.ok(!httpSignature.verify(parsed, ecdsaPublic));
+
+    res.writeHead(200);
+    res.write(JSON.stringify(parsed, null, 2));
+    res.end();
+  };
+
+  options.headers.Date = jsprim.rfc1123(new Date());
+  options.headers.Authorization =
+      'Signature keyId="foo",algorithm="hs2019",signature="' +
+      uuid() + '"';
+
+  http.get(options, function(res) {
+    t.equal(res.statusCode, 200);
+    t.end();
+  });
+});
+
+test('invalid hs2019 (valid ecdsa-sha256)', function(t) {
+  server.tester = function(req, res) {
+    var parsed = httpSignature.parseRequest(req);
+    t.ok(!httpSignature.verify(parsed, ecdsaPublic));
+
+    res.writeHead(200);
+    res.write(JSON.stringify(parsed, null, 2));
+    res.end();
+  };
+
+  options.headers.Date = jsprim.rfc1123(new Date());
+  var key = sshpk.parsePrivateKey(ecdsaPrivate);
+  var signer = key.createSign('sha256');
+  signer.update('date: ' + options.headers.Date);
+  options.headers.Authorization =
+      'Signature keyId="foo",algorithm="hs2019",signature="' +
+      signer.sign().toString() + '"';
+
+  http.get(options, function(res) {
+    t.equal(res.statusCode, 200);
+    t.end();
+  });
+});
+
+test('valid hs2019 (valid ecdsa-sha512)', function(t) {
+  server.tester = function(req, res) {
+    var parsed = httpSignature.parseRequest(req);
+    t.ok(httpSignature.verify(parsed, ecdsaPublic));
+
+    res.writeHead(200);
+    res.write(JSON.stringify(parsed, null, 2));
+    res.end();
+  };
+
+  options.headers.Date = jsprim.rfc1123(new Date());
+  var key = sshpk.parsePrivateKey(ecdsaPrivate);
+  var signer = key.createSign('sha512');
+  signer.update('date: ' + options.headers.Date);
+  options.headers.Authorization =
+      'Signature keyId="foo",algorithm="hs2019",signature="' +
+      signer.sign().toString() + '"';
+
+  http.get(options, function(res) {
+    t.equal(res.statusCode, 200);
+    t.end();
+  });
+});
+
+test('valid hs2019 (valid dsa-sha512)', function(t) {
+  server.tester = function(req, res) {
+    var parsed = httpSignature.parseRequest(req);
+    t.ok(httpSignature.verify(parsed, dsaPublic));
+
+    res.writeHead(200);
+    res.write(JSON.stringify(parsed, null, 2));
+    res.end();
+  };
+
+  options.headers.Date = jsprim.rfc1123(new Date());
+  var key = sshpk.parsePrivateKey(dsaPrivate);
+  var signer = key.createSign('sha512');
+  signer.update('date: ' + options.headers.Date);
+  options.headers.Authorization =
+      'Signature keyId="foo",algorithm="hs2019",signature="' +
+      signer.sign().toString() + '"';
+
+  http.get(options, function(res) {
+    t.equal(res.statusCode, 200);
+    t.end();
+  });
+});
+
+test('valid hs2019 (valid rsa-sha512)', function(t) {
+  server.tester = function(req, res) {
+    var parsed = httpSignature.parseRequest(req);
+    t.ok(httpSignature.verify(parsed, rsaPublic));
+
+    res.writeHead(200);
+    res.write(JSON.stringify(parsed, null, 2));
+    res.end();
+  };
+
+  options.headers.Date = jsprim.rfc1123(new Date());
+  var signer = crypto.createSign('RSA-SHA512');
+  signer.update('date: ' + options.headers.Date);
+  options.headers.Authorization =
+      'Signature keyId="foo",algorithm="hs2019",signature="' +
+      signer.sign(rsaPrivate, 'base64') + '"';
+
+  http.get(options, function(res) {
+    t.equal(res.statusCode, 200);
+    t.end();
+  });
+});
+
+
 test('invalid date', function(t) {
   server.tester = function(req, res) {
     t.throws(function() {