diff --git a/hws/middleware.go b/hws/middleware.go
index 4a70ede..e9f0064 100644
--- a/hws/middleware.go
+++ b/hws/middleware.go
@@ -10,11 +10,14 @@ type MiddlewareFunc func(w http.ResponseWriter, r *http.Request) (*http.Request,
 
 // Server.AddMiddleware registers all the middleware.
 // Middleware will be run in the order that they are provided.
+// Can only be called once
 func (server *Server) AddMiddleware(middleware ...Middleware) error {
 	if !server.routes {
 		return errors.New("Server.AddRoutes must be called before Server.AddMiddleware")
 	}
-
+	if server.middleware {
+		return errors.New("Server.AddMiddleware already called")
+	}
 	// RUN LOGGING MIDDLEWARE FIRST
 	server.server.Handler = logging(server.server.Handler, server.logger)