Two complementary programs are described, dealing with the prediction of coupling between wires. The first (CABCIP) is intended for the design of the entire wiring of large systems. The program produces recommendations on the type of wire to use (single, twisted-pair, shielded, etc); on the harness to which the wire should belong and the separation between harnesses. The program is iterative, advancing in three stages as available data increases. Realistic worst-case default values are used for parameters that are not known in the early stages of a design. The other program (IPFCBW) is a simplified version of CABCIP, intended for rapid interactive use.