A graduate of Emerson College, Spiro has worked as a director, actor and teacher in the Boston area for the last 25 years. He has been a company member of the Boston and National Shakespeare companies, playing such varied roles as Nick the Bartender in Time of Your Life to Prospero in The Tempest. In 1981 he became the artistic director of the Publick Theatre, Inc. a position he held until last summer. With the Publick Theatre he received the 1986 Boston Critics' Circle Award for Outstanding Direction and Production for A Midsummer Night's Dream; The New England Theatre Conference's Moss Hart Award for the New England Premiere of the musical Quilters; the 1996 Boston Theatre Award of Outstanding Direction for Anything Goes and Sweeney Todd.

As a guest director with the Lyric Stage, his production of David Mamet's Speed-the-Plow was honored with the 1997 Elliot Norton Award for Outstanding Production. He has directed over 60 professional productions in Boston as well as regionally with the Seacoast Repertory Theatre in Portsmouth, New Hampshire, where his recent production of Sweeney Todd received the 1999 Spotlight on the Arts readers poll award for Best Musical. Productions that he has directed have been named to at least 25 "Best of the Year" lists. In 1991 the Boston City Council gave him a special citation for continued service to the Boston community.

Some of his own favorite productions are: She Loves Me, Butley, American Buffalo, Much Ado About Nothing, Gypsy, Guys and Dolls, The Judas Kiss, Into the Woods, Cyrano de Bergerac, Inherit the Wind and Cat on a Hot Tin Roof.