Abstract
Two octocoral families, the Paramuriceidae and Plexauridae, are revised and their twenty-four Hawaiian species are described. Eighteen of the twenty-four species are new; all are illustrated with drawings and scanning electron micrographs. Observed during submarine dives, their deep-water habitat is characterized by firm substrate, moderate currents, and stable temperatures. Their zoogeography resembles other Hawaiian marine organisms, exhibiting endemism and attenuation. Their closest relationship at the specific level is to the Indo-West Pacific.