diff --git a/s3-upload-stream/index.d.ts b/s3-upload-stream/index.d.ts
index 382c3a57f1..be8de4148a 100644
--- a/s3-upload-stream/index.d.ts
+++ b/s3-upload-stream/index.d.ts
@@ -9,14 +9,16 @@
 import * as stream from 'stream';
 import * as AWS from 'aws-sdk';
 
-interface S3StreamUploader {
-    upload(destinationDetails: AWS.s3.PutObjectRequest, sessionDetails?: any): S3WriteStream;
+declare namespace s3Stream {
+    export interface S3StreamUploader {
+        upload(destinationDetails: AWS.s3.PutObjectRequest, sessionDetails?: any): S3WriteStream;
+    }
+
+    export interface S3WriteStream extends stream.Writable {
+        maxPartSize(sizeInBytes: number): void;
+        concurrentParts(numberOfParts: number): void;
+    }
 }
 
-interface S3WriteStream extends stream.Writable {
-    maxPartSize(sizeInBytes: number): void;
-    concurrentParts(numberOfParts: number): void;
-}
-
-declare function s3Stream(client: AWS.S3): S3StreamUploader;
+declare function s3Stream(client: AWS.S3): s3Stream.S3StreamUploader;
 export = s3Stream;