Rods & Cones
Located in the Bay area of Northern Califonia, Rods and Cones is a consultancy that is staffed with very knowledgeable folks. They are very active and involved in color, and help host the Northern California Colorsync Users Group. They service mostly corporate and photographer needs.
Previously located in Boulder, Cololrado, (and now relocating to Manhattan) Chris Murphy is a consultant who is a very valuable resource. He has a knack for identifing bugs in color management software, and then giving manufacturers living hell for it on the tradeshow/lecture ciruit. His knowledge is excellent, and he is one of the personalities that help push the technology forward. Look for the second edition of his book on color management written by Chris, Bruce Fraser, and Fred Bunting soon to be on bookshelves.