This grant funds the development of electrical models of the interconnections in Multichip Modules (MCMs) that are useful at Gigahertz frequencies. At these frequencies the interconnections have a significant if not dominant effect. MCMs are the next generation packaging technique. Better MCM models are needed to exploit the opportunities that MCMs offer for essential enhancements in the performance of both analog and digital electronics. The models will be obtained from experimental, analytical, and simulation studies. The outcome will be tables with routines for interpolation that can be imbedded in MCM design rules and invoked by separate MCM CAD tools.