diff --git a/types/react-transition-group/CSSTransition.d.ts b/types/react-transition-group/CSSTransition.d.ts
index 8d48a48ce8..1192badcea 100644
--- a/types/react-transition-group/CSSTransition.d.ts
+++ b/types/react-transition-group/CSSTransition.d.ts
@@ -5,6 +5,7 @@ declare namespace CSSTransition {
     interface CSSTransitionClassNames {
         appear?: string;
         appearActive?: string;
+        appearDone?: string;
         enter?: string;
         enterActive?: string;
         enterDone?: string;
diff --git a/types/react-transition-group/index.d.ts b/types/react-transition-group/index.d.ts
index de0e099b14..72773ff9db 100644
--- a/types/react-transition-group/index.d.ts
+++ b/types/react-transition-group/index.d.ts
@@ -1,4 +1,4 @@
-// Type definitions for react-transition-group 2.8
+// Type definitions for react-transition-group 2.9
 // Project: https://github.com/reactjs/react-transition-group
 // Definitions by: Karol Janyst <https://github.com/LKay>
 //                 Epskampie <https://github.com/Epskampie>
diff --git a/types/react-transition-group/react-transition-group-tests.tsx b/types/react-transition-group/react-transition-group-tests.tsx
index f568642a90..e804df1133 100644
--- a/types/react-transition-group/react-transition-group-tests.tsx
+++ b/types/react-transition-group/react-transition-group-tests.tsx
@@ -110,6 +110,7 @@ const Test: React.StatelessComponent = () => {
                 classNames={ {
                     appear: "fade-appear",
                     appearActive: "fade-active-appear",
+                    appearDone: "fade-done-appear",
                     enter: "fade-enter",
                     enterActive: "fade-active-enter",
                     enterDone: "fade-done-enter",