diff --git a/types/forge-viewer/index.d.ts b/types/forge-viewer/index.d.ts
index f196c0c41c..32cd3c8a90 100644
--- a/types/forge-viewer/index.d.ts
+++ b/types/forge-viewer/index.d.ts
@@ -566,6 +566,8 @@ declare namespace Autodesk {
         }
 
         class Viewer3D {
+            constructor(container: HTMLElement, config?: Viewer3DConfig);
+
             id: number;
             activateLayerState(stateName: string): void;
             activateExtension(extensionID: string, mode: string): boolean;