diff --git a/lodash/lodash-tests.ts b/lodash/lodash-tests.ts
index 01aedc432c..7db984bcca 100644
--- a/lodash/lodash-tests.ts
+++ b/lodash/lodash-tests.ts
@@ -8152,6 +8152,31 @@ module TestFunctions {
     }
 }
 
+// _.functionsIn
+module TestFunctionsIn {
+    type SampleObject = {a: number; b: string; c: boolean;};
+
+    let object: SampleObject;
+
+    {
+        let result: string[];
+
+        result = _.functionsIn<SampleObject>(object);
+    }
+
+    {
+        let result: _.LoDashImplicitArrayWrapper<string>;
+
+        result = _(object).functionsIn();
+    }
+
+    {
+        let result: _.LoDashExplicitArrayWrapper<string>;
+
+        result = _(object).chain().functionsIn();
+    }
+}
+
 // _.get
 result = <number>_.get<number>({ 'a': [{ 'b': { 'c': 3 } }] }, 'a[0].b.c');
 
diff --git a/lodash/lodash.d.ts b/lodash/lodash.d.ts
index 3f596a202c..e27022b9cd 100644
--- a/lodash/lodash.d.ts
+++ b/lodash/lodash.d.ts
@@ -99,9 +99,9 @@ added 18 lang methods:
 - [ ] _.toString
 
 added 13 object methods:
-- [ ] _.assignIn
-- [ ] _.assignInWith
-- [ ] _.assignWith
+- [x] _.assignIn
+- [x] _.assignInWith
+- [x] _.assignWith
 - [ ] _.functionsIn
 - [ ] _.hasIn
 - [ ] _.invoke
@@ -13009,10 +13009,25 @@ declare module _ {
     //_.functions
     interface LoDashStatic {
         /**
-         * Creates an array of function property names from all enumerable properties, own and inherited, of object.
+         * Creates an array of function property names from own enumerable properties
+         * of `object`.
          *
-         * @param object The object to inspect.
-         * @return Returns the new array of property names.
+         * @static
+         * @memberOf _
+         * @category Object
+         * @param {Object} object The object to inspect.
+         * @returns {Array} Returns the new array of property names.
+         * @example
+         *
+         * function Foo() {
+         *   this.a = _.constant('a');
+         *   this.b = _.constant('b');
+         * }
+         *
+         * Foo.prototype.c = _.constant('c');
+         *
+         * _.functions(new Foo);
+         * // => ['a', 'b']
          */
         functions<T extends {}>(object: any): string[];
     }
@@ -13031,6 +13046,46 @@ declare module _ {
         functions(): _.LoDashExplicitArrayWrapper<string>;
     }
 
+    //_.functionsIn
+    interface LoDashStatic {
+        /**
+         * Creates an array of function property names from own and inherited
+         * enumerable properties of `object`.
+         *
+         * @static
+         * @memberOf _
+         * @category Object
+         * @param {Object} object The object to inspect.
+         * @returns {Array} Returns the new array of property names.
+         * @example
+         *
+         * function Foo() {
+         *   this.a = _.constant('a');
+         *   this.b = _.constant('b');
+         * }
+         *
+         * Foo.prototype.c = _.constant('c');
+         *
+         * _.functionsIn(new Foo);
+         * // => ['a', 'b', 'c']
+         */
+        functionsIn<T extends {}>(object: any): string[];
+    }
+
+    interface LoDashImplicitObjectWrapper<T> {
+        /**
+         * @see _.functionsIn
+         */
+        functionsIn(): _.LoDashImplicitArrayWrapper<string>;
+    }
+
+    interface LoDashExplicitObjectWrapper<T> {
+        /**
+         * @see _.functionsIn
+         */
+        functionsIn(): _.LoDashExplicitArrayWrapper<string>;
+    }
+
     //_.get
     interface LoDashStatic {
         /**