This correspondence addresses actual implementation of a multiway fan-out and its effect on test generation. If a test generation ignores the fan-out implementation faults may be left undetected by the test set. Moreover, different implementations of the multiway fan-out may lead to different fault coverages. Careless implementation of the fan-out may also yield undetectable faults. Some guidelines for fan-out implementation that may enhance testability are given in this correspondence. Copyright © 1985 by The Institute of Electrical and Electronics Engineers, Inc.