The Star Trek Encyclopedia: A Reference Guide to the Future, written by Star Trek staffers Mike and Denise Okuda with Debbie Mirek, is one of a triumvirate of reference books (the others being The Star Trek Chronology: A History of the Future and The Star Trek: The Next Generation Technical Manual) that focus on the Star Trek universe.

Unlike Allan Asherman's The Star Trek Compendium (essentially a guide to the original series' episodes and feature film incarnations), the conceit of these books is that they are presented as though the Star Trek universe really existed. Written from a "24th-Century point of view," the entries read as though they had been composed by historians chronicling the events and scientific developments in Federation history. As the introduction explains, "we have assumed editorially that both authors and readers are residents of the late 24th century" a few years after some of the latter series' (Star Trek: The Next Generation for the first 1994 edition) runs.

Although the Okudas considered using "facts" from some of the many authorized Star Trek novels published by Pocket Books, they decided to limit their entries to data taken directly from The Original Series, the feature films and the various television spin-offs. Thus, while there is an entry for Zarabeth (who appeared in TOS episode "All Our Yesterdays"), there is none for Zar, the son Spock fathered during his brief fling with her on Sarpeidon (and who appeared only in A.C. Crispin's novels Yesterday's Son and Time for Yesterday). It would have been difficult for the compilers of the Encyclopedia to choose which "facts" to include and which ones to exclude, so all the entries are about people, planets, weapons, life forms, civilizations and starships seen on film or video. (NBC/Filmation's 1970s Star Trek animated series is also excluded because it was not produced by Paramount.)

As in Steven Sansweet's 1998 Star Wars Encyclopedia, the entries are presented in alphabetical order from A ("A&A Officer") to Z ("Zytchin III"). Many entries are short and to the point; there are no long, detailed articles about the workings of a hand phaser or the intricacies of the transporter (that's in Rick Sternbach and Mike Okuda's Star Trek: The Next Generation Technical Manual). The longer entries focus, appropriately, on the major characters (such as Kirk, Spock and Picard). All the actors who portrayed onscreen characters are properly credited in parentheses, and the episode or film where data points are derived from are also identified.

In addition to still photos from episodes and feature films, The Star Trek Encyclopedia is replete with charts, graphs and line drawings of starships, uniforms, equipment, weapons, and Starfleet signage and insignia.

Even more enjoyable are the authors' "real-life" observations that, like their text commentaries on the new Collector's Edition Star Trek feature film DVDs, give the reader insights that are both informative and amusing. The entire series of "official reference works" has these little gems that reflect the wonder and genuine affection that the authors -- and the fans -- have for the various incarnations of Roddenberry's optimistic look at the future.