diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6ad8786fe14..11bfbf6fb41 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,8 @@ The version headers in this history reflect the versions of Apollo Server itself
 
 > The changes noted within this `vNEXT` section have not been released yet.  New PRs and commits which introduce changes should include an entry in this `vNEXT` section as part of their development.  When a release is being prepared, a new header will be (manually) created below and the the appropriate changes within that release will be moved into the new section.
 
+- `apollo-server-plugin-base`: Fix `GraphQLRequestListener` type definitions to allow `return void`. [PR #2368](https://github.com/apollographql/apollo-server/pull/2368)
+
 ### v2.6.7
 
 > [See complete versioning details.](https://github.com/apollographql/apollo-server/commit/183de5f112324def375a45c239955e1bf1608fae)
diff --git a/packages/apollo-server-plugin-base/src/index.ts b/packages/apollo-server-plugin-base/src/index.ts
index ecc7ca5ec0f..6a15a7839f4 100644
--- a/packages/apollo-server-plugin-base/src/index.ts
+++ b/packages/apollo-server-plugin-base/src/index.ts
@@ -29,13 +29,13 @@ export interface GraphQLRequestListener<TContext = Record<string, any>> {
       GraphQLRequestContext<TContext>,
       'metrics' | 'source'
     >,
-  ): (err?: Error) => void | void;
+  ): ((err?: Error) => void) | void;
   validationDidStart?(
     requestContext: WithRequired<
       GraphQLRequestContext<TContext>,
       'metrics' | 'source' | 'document'
     >,
-  ): (err?: ReadonlyArray<Error>) => void | void;
+  ): ((err?: ReadonlyArray<Error>) => void) | void;
   didResolveOperation?(
     requestContext: WithRequired<
       GraphQLRequestContext<TContext>,
@@ -64,7 +64,7 @@ export interface GraphQLRequestListener<TContext = Record<string, any>> {
       GraphQLRequestContext<TContext>,
       'metrics' | 'source' | 'document' | 'operationName' | 'operation'
     >,
-  ): (err?: Error) => void | void;
+  ): ((err?: Error) => void) | void;
   willSendResponse?(
     requestContext: WithRequired<
       GraphQLRequestContext<TContext>,