A set of CASE tools is described for developing formal requirements specifications expressed in the SCR (Software Cost Reduction) tabular notation. The tools include an editor for building the specifications, a consistency checker for testing the specifications for consistency with a formal requirements model, a simulator for symbolically executing the specifications, and a verifier for checking that the specifications satisfy selected application properties. As background, the SCR method for specifying requirements is reviewed, and a formal requirements model is introduced. Examples are presented to illustrate the tools.