The Museum of Primitive Art and the artistic traditions it presented gained acceptance as it grew. Acquisitions continued at a steady pace to reach 3,500 works that were included in the growing lineup of exhibitions and publications. The 54th Street building where the Museum of Primitive Art had been housed since its opening was full of works, books, and staff members, and by the end of the 1960s it had become clear that it needed to become part of something else or become something else.
On May 10, 1969, an exhibition of the Museum of Primitive Art's collection opened at The Metropolitan Museum of Art. Titled Art of Oceania, Africa, and the Americas from The Museum of Primitive Art, it featured eight hundred works displayed in more than seventeen rooms and was described at the time as "the most important exhibition of primitive art ever held." During the press conference, Governor Rockefeller announced that the collection of his museum would be integrated into that of the Metropolitan. That year, to punctuate the end of an era, Rockefeller made his final important acquisition of Precolumbian art: the ensemble of more than one hundred gold, silver, and copper ornaments from the Moche Loma Negra culture. It took thirteen years for the Michael C. Rockefeller Wing to be built; its galleries opened to the public in 1982.