He is a graduate of the Yale University School of Drama, and is a member of Actors Equity Association and Screen Actors Guild. Gewirtz was creator and Artistic Director of Liberty Stage Company and co-author of Trelawny of the 'Wells' (Now and Then), an adaptation depicting contemporary actors rehearsing the 1898 play by Sir Arthur Wing Pinero. Since 2000, he has been the Director and Producer of The 4th Wall Actors Workshop in New York City. At NYUSPS since 1999, Gewirtz currently teaches Acting in "The Zone": Scene Study and Improvisation, Beginning Acting Boot Camp, and A Taste of Acting. He is the recipient of the NYUSPS Teaching Excellence Award (2010).