The authors describe scan path, NEC's implementation of the scan design approach to design for testability. Designers at NEC have found that scan path greatly contributes to the reduced testing and maintenance cost of their products. The authors discuss several implementations of scan design and compare four implementations, including two scan-path techniques.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>