The first edition of Taper's Balanchine biography--expanded from a New Yorker profile, partly based on six years of conversations with the choreographer himself--appeared in 1963. Ten years later a new chapter (another New Yorker profile) was added--covering a week in August 1973, while touching briefly on such matters as the 1972 Stravinksy Festival, Melissa Hayden's swan-song, and the departure of Suzanne Farrell (the object of ""a preoccupation amounting to an obsession"" for Balanchine). And now, again ten years later, in addition to making changes throughout, Taper has included three new chapters, with fresh interview-material from NYCB dancers and informal, often sketchy treatment of: Peter Martins' arrival and ascent (with a few fine anecdotes to reflect the Martins/Balanchine relationship); the return of Suzanne Farrell; the 1976 and 1980 strikes, the latter felt by Mr. B. as ""a personal repudiation""; the Baryshnikov experiment; the late ballets, including the controversially revised Apollo; Balanchine's ""strong attachment"" to Karin von Aroldingen; and his increasing, ultimately fatal problems with heart-trouble and a rare neurological disease. All in all, this post-1963 material falls far short of what one expects from a so-called ""definitive biography."" Throughout, too, Taper's study is seriously limited by his interested-amateur approach to Balanchine's work. Still: a graceful, informative, impressionistic portrait--far from authoritative, perhaps, but rich in personality.