In the mid-’70s, 20-year-old Michael Feinstein was hired to be Ira Gershwin’s assistant and archivist. Impressed by the young man’s knowledge of his and his late brother George’s music, the iconic lyricist asked: “How many more of you are there?” The gig blossomed into a friendship that lasted until Gershwin’s death in 1983.

Feinstein, a singer, songwriter, pianist, and educator, has a new book titled “The Gershwins and Me: A Personal History in Twelve Songs.” We chatted by phone with Feinstein, who has a local connection as a member of the American Repertory Theater board of trustees.