When Hirshhorn began to make money, he began to buy art, both paintings and sculpture. He amassed a collection of paintings and sculptures from the 19th and 20th centuries. Applying himself seriously to the study of art, he would question dealers, critics, and curators, and visit artists in their studios. He made quick decisions on buying a piece. "If you've got to look at a picture a dozen times before you make up your mind", he once said, "there's something wrong with you or the picture".