Abstract.The current generation of CASE (Computer Aided Software Engineering) tools is too inflexible to provide adequate modelling support. One of the proposed solutions to this problem is the development of so‐called CASE shells. A CASE shell is a method independent CASE tool, which may be instantiated with a specific method to become a CASE tool supporting that method. As such, a CASE shell provides complete flexibility. This paper does not address the benefits of CASE shells, as they are completely clear, but focuses on the feasibility of this concept from a theoretical as well as a practical point of vi