Knaster is an active philanthropist, who has made significant contributions to different academic institutions, including Carnegie Mellon University and Harvard Business School, where he serves as a regional Campaign Leadership volunteer. In 1993, Knaster established the Alexander M. Knaster Scholarship Fund for undergraduates in the Department of Electrical and Computer Engineering at Carnegie Mellon University. In 2011, in partnership with fellow alumnus Bruce McWilliams, Knaster helped to establish the Knaster-McWilliams scholarships, which allow for increased access to faculty and early research opportunities in addition to tuition assistance. The Alexander M. Knaster Professorship in Mathematical sciences is named in his honor.