This paper describes the development of a knowledge-based system to as
sist Southern California Edison (SCE) in the design of electric servic
e facilities for residential developments. The system supports SCE pla
nners both by performing spatial reasoning in support of the design ta
sk and by performing more routine parts of the design. The paper also
outlines the technical issues underlying how this knowledge-based desi
gner's assistant is being integrated into the CADD environment current
ly being used throughout the SCE grid.