After Brooklyn Academy of Music's first building on Montague street burned in 1903, Brooklyn Borough President Martin W. Littleton led an effort that brought prominent Brooklynites to the task of rehousing Brooklyn's cultural Academy and its educational partner the Brooklyn Institute. Within five years, theater architects Herts and Tallant had built a massive but programatically flexible structure on Lafayette Avenue, a multi-story building with a main facade in the Beaux Arts style. Littleton summarized the mission of the new space:
"…a place where our ever-swelling population might gather to gratify its passion for music, to satisfy its thirst for knowledge, to minister to its love for social communion and to appeal to its patriotism in the great struggles of popular politics."

To the goal of social communion, the design included a 5,000 square foot grand foyer where audience members circulated before entering their respective venues. The major space in the building is the grand opera house, featuring two balconies and 2,200 seats. A concert hall, used for both musical concerts and lectures, had its entrance from the main lobby. This space has been subdivided into several movie theaters, but much of the original detail has been preserved. An ornate ballroom on the second floor was redesigned in 1973 as the Lepercq Space, an enormous "black box" theater, that was again redesigned in 1997 as a multi-purpose space housing BAMcafé. Part of the third floor, above the concert hall and to the east of the third balcony of the opera house, was reserved for the Brooklyn Institute's classrooms, offices, and a 400-seat lecture hall. The halls, offices, and classroom spaces still exist, but the lecture hall has been transformed into offices.

The inaugural gala featured Enrico Caruso and Geraldine Farrar, Franklin D. Roosevelt spoke in 1940, Rudolf Nureyev made his American debut in 1962 - since the beginning, BAM's main building has witnessed history-making performances and lectures by a who's who of artists, historical figures, and officials. It has far exceeded its grand turn-of-the century mission, becoming in addition the home for adventurous artists, audiences, and ideas.