diff --git a/InstallModuleFromGitHub.psm1 b/InstallModuleFromGitHub.psm1
index 5dfdb83..dd07c85 100644
--- a/InstallModuleFromGitHub.psm1
+++ b/InstallModuleFromGitHub.psm1
@@ -8,6 +8,8 @@ function Install-ModuleFromGitHub {
         $DestinationPath,
         $SSOToken,
         $moduleName,
+        [ValidateSet('CurrentUser','AllUsers')]
+        [string]
         $Scope
     )