diff --git a/src/OidcClient.js b/src/OidcClient.js
index b5b69fa0..bc22b799 100644
--- a/src/OidcClient.js
+++ b/src/OidcClient.js
@@ -63,6 +63,7 @@ export class OidcClient {
         resource = resource || this._settings.resource;
         response_mode = response_mode || this._settings.response_mode;
         extraQueryParams = extraQueryParams || this._settings.extraQueryParams;
+        extraTokenParams = extraTokenParams || this._settings.extraTokenParams;
 
         let authority = this._settings.authority;
 
diff --git a/src/OidcClientSettings.js b/src/OidcClientSettings.js
index 1fdba17c..de6ded54 100644
--- a/src/OidcClientSettings.js
+++ b/src/OidcClientSettings.js
@@ -31,7 +31,8 @@ export class OidcClientSettings {
         ResponseValidatorCtor = ResponseValidator,
         MetadataServiceCtor = MetadataService,
         // extra query params
-        extraQueryParams = {}
+        extraQueryParams = {},
+        extraTokenParams = {}
     } = {}) {
 
         this._authority = authority;
@@ -65,6 +66,7 @@ export class OidcClientSettings {
         this._metadataService = new MetadataServiceCtor(this);
 
         this._extraQueryParams = typeof extraQueryParams === 'object' ? extraQueryParams : {};
+        this._extraTokenParams = typeof extraTokenParams === 'object' ? extraTokenParams : {};
     }
 
     // client config
@@ -204,4 +206,16 @@ export class OidcClientSettings {
             this._extraQueryParams = {};
         }
     }
+
+    // extra token params
+    get extraTokenParams() {
+        return this._extraTokenParams;
+    }
+    set extraTokenParams(value) {
+        if (typeof value === 'object'){
+            this._extraTokenParams = value;
+        } else {
+            this._extraTokenParams = {};
+        }
+    }
 }
diff --git a/test/unit/OidcClientSettings.spec.js b/test/unit/OidcClientSettings.spec.js
index f6ffe351..1d9cd6d2 100644
--- a/test/unit/OidcClientSettings.spec.js
+++ b/test/unit/OidcClientSettings.spec.js
@@ -459,4 +459,51 @@ describe("OidcClientSettings", function () {
         });
     })
 
+    describe("extraTokenParams", function() {
+
+        it("should use default value", function () {
+            let subject = new OidcClientSettings({
+                client_id: 'client'
+            });
+            subject.extraTokenParams.should.deep.equal({});
+        });
+
+        it("should return value from initial settings", function () {
+            let subject = new OidcClientSettings({
+                client_id: 'client',
+                extraTokenParams: {
+                    'resourceServer': 'abc'
+                }
+            });
+            subject.extraTokenParams.should.deep.equal({ 'resourceServer': 'abc' });
+        });
+
+        it("should not set value from initial settings if not object, but set default value ({})", function () {
+            let subject = new OidcClientSettings({
+                client_id: 'client',
+                extraTokenParams: 123456
+            });
+            subject.extraTokenParams.should.deep.equal({});
+        });
+
+        it("should set it if object", function () {
+            let subject = new OidcClientSettings({
+                client_id: 'client',
+            });
+            subject.extraTokenParams = { 'resourceServer': 'abc' };
+            subject.extraTokenParams.should.deep.equal({ 'resourceServer': 'abc' });
+        });
+
+        it("should clear it if not object", function() {
+            let subject = new OidcClientSettings({
+                client_id: 'client',
+                extraTokenParams: {
+                    'resourceServer': 'abc',
+                }
+            });
+            subject.extraTokenParams = undefined;
+            subject.extraTokenParams.should.deep.equal({});
+        });
+    })
+
 });
diff --git a/test/unit/SigninRequest.spec.js b/test/unit/SigninRequest.spec.js
index ca4fa125..103d42b7 100644
--- a/test/unit/SigninRequest.spec.js
+++ b/test/unit/SigninRequest.spec.js
@@ -202,6 +202,16 @@ describe("SigninRequest", function() {
             subject.url.should.contain('hd=domain.com&foo=bar');
         });
 
+        it("should store extra token params in state", function() {
+            settings.extraTokenParams = {
+                'resourceServer': 'abc',
+            };
+            subject = new SigninRequest(settings);
+            assert.deepEqual(subject.state.extraTokenParams, {
+                'resourceServer': 'abc'
+            });
+        });
+
         it("should include code flow params", function() {
             settings.response_type = "code";
             subject = new SigninRequest(settings);
diff --git a/test/unit/SigninState.spec.js b/test/unit/SigninState.spec.js
index 8486cdbf..ed2583bf 100644
--- a/test/unit/SigninState.spec.js
+++ b/test/unit/SigninState.spec.js
@@ -68,6 +68,11 @@ describe("SigninState", function() {
             var subject = new SigninState({ request_type: 'xoxo' });
             subject.request_type.should.be.equal('xoxo');
         });
+
+        it("should accept extraTokenParams", function() {
+            var subject = new SigninState({ extraTokenParams: { 'resourceServer' : 'abc' } });
+            assert.deepEqual(subject.extraTokenParams, { 'resourceServer' : 'abc' });
+        });
     });
 
     it("can serialize and then deserialize", function() {