Ensemble Studio Theatre's reputation as a place to develop new work is perhaps best borne out by their annual OctoberFest, which features everything from full productions to staged works-in-progress to first readings.

The 17th annual event runs Sept. 30-Oct. 26 at E.S.T.'s West 59th St. home and features over 50 pieces by such writers as Bill Bozzone, David Mamet, Keith Reddin and Pennell Somsen.

All offerings are free but require reservations. For a full schedule of events call (212) 247-4982.

Among the pieces in OctoberFest 1997 are Egg Yolk In A Pool Of Aqua Velva, by Bill Cwikowski; The Jade Mountain, by David Mamet; Short, Fast And Funny by Marilyn Rockafellow; Bright Enigma by Leslie Lee; Haiti by Keith Reddin; The F Word by Pennell Somsen; Leo Sideways by Bill Bozzone; The Last Trial Of Clarence Darrow by Shirley Lauro; and Gint, an Ibsen adaptation by Romulus Linney.

E.S.T.'s next full-length project will be Flight, a drama about the Wright Brothers by Arthur Giron. Jamie Richards, who staged Stonewall Jackson's House, will direct the piece, Nov. 11-Dec. 7. Founder Kurt Dempster serves as artistic director of E.S.T., started in 1971 as a theatre home for playwrights, directors, actors and designers.

--By David Lefkowitz