For five years he worked in the San Francisco Opera, being responsible for acquiring company's records collection.
As author, he wrote such books on music and operatic composers as: Wagner Without Fear (1998), Verdi With a Vengeance (2000), Puccini Without Excuses (2005), all published by Random House.
He has also written opera libretti and articles on religion and architecture.
Since creation of the Metropolitan Opera Radio on Sirius in the Fall of 2006, he writes all the commentaries heard during entractes of historical broadcasts.
Berger is currently often a co-host during live Metropolitan Opera radio broadcasts, and is often the moderator of those broadcasts' Met Opera Quiz.