Method configuration (MC) has been presented as a particular kind of method engineering (ME). ME in general is often a tedious and time consuming task and method configuration is no exception. Consequently, tool support is often required. In this paper we present an operationalization of the Method for Method Configuration into the tool support MC Sandbox. The functionality in MC Sandbox emphasizes reusable method assets and MC based on methods’ rationale. The latter is usually not considered as an explicit focal area within ME. Furthermore, we present the experiences from the first workshop where the MC Sandbox has been successfully used during configuration work, and the repercussions it has on the design of the tool and the meta-method.