diff --git a/docs/system-api.md b/docs/system-api.md
index ea2d9643..b6a49c10 100644
--- a/docs/system-api.md
+++ b/docs/system-api.md
@@ -138,6 +138,11 @@ SystemJS registry object supporting:
 
 See also [SystemJS.newModule](#systemjsnewmoduleobject---module).
 
+#### SystemJS.resolveSync(moduleName)
+Type: `Function`
+
+Resolves module name to normalized URL.
+
 #### SystemJS.set(moduleName, Module)
 Type: `Function`