Marc Okrand devised the dialogue and coached the actors speaking the Klingon language heard in "Star Trek III: The Search For Spock," "Star Trek V: The Final Frontier," "Star Trek VI: The Undiscovered Country," and "Star Trek Into Darkness." He also created the Atlantean language heard in the Walt Disney animated feature "Atlantis: The Lost Empire." The Klingon language he developed has been used in a number of episodes of "Star Trek: The Next Generation," "Star Trek: Deep Space Nine," "Star Trek: Voyager," and "Star Trek: Enterprise." In addition, he created the Vulcan dialogue for "Star Trek II: The Wrath of Khan" and "Star Trek III," and both Vulcan and Romulan dialogue for 2009’s "Star Trek."
He is the author of "The Klingon Dictionary" (Pocket Books, 1985; revised edition, 1992), an introduction to the grammar and vocabulary of the language; "The Klingon Way: A Warrior's Guide" (Pocket Books, 1996), an annotated compilation of Klingon proverbs; and "Klingon For the Galactic Traveler" (Pocket Books, 1997), a guide to the finer points of the Klingon language, including specialized terminology, slang, idioms, dialects. He can be heard describing various aspects of the language and its effective use on the audio books "Conversational Klingon" (Simon & Schuster Audioworks, 1992) and "Power Klingon" (co-written with Barry Levine, Simon & Schuster Audioworks, 1993), both narrated by Michael Dorn. He also devised Klingon dialogue and contributed to the language lab portion of the computer game "Star Trek: Klingon" (Simon & Schuster Interactive, 1996). He did the translation for the Klingon opera ’u’ that premiered in The Netherlands in September 2010 as well as the expanded version of the opera’s story in "paq’batlh: The Klingon Epic" (Uitgevrij, 2011). He co-wrote the chapter on Klingon in "From Elvish to Klingon: Exploring Invented Languages" by Michael Adams (Oxford University Press, 2011), and contributed to the Klingon version of Monopoly and the instructional DVD "Learn Klingon" (EuroTalk, 2011). He is an associate producer of the forthcoming documentary film "Conlanging: The Art of Crafting Tongues."
He has a BA in linguistics from the University of California, Santa Cruz (1970) and a Ph.D. in linguistics from the University of California, Berkeley (1977) and has conducted linguistic research as a postdoctoral fellow at the Smithsonian Institution in Washington, D.C. His linguistic research has focused primarily on native languages of California, in particular the Ohlonean languages of the central California coast.
He is a member of the board of directors of the theater company WSC Avant Bard in Arlington, Virginia. For 34 years, up until his retirement, he helped manage the closed captioning of various network and syndicated television programs. In addition to his published work on Klingon, he has written articles on both linguistics and closed captioning for several journals and anthologies.