Cassat was an outspoken advocate for women's equality, campaigning with her friends for equal travel scholarships for students in the 1860s, and the right to vote in the 1910s.
Cassatt var uforbeholden fortaler for kvinders ligeberettigelse og talte sammen med sine venner for lige rejselegater for studenter i 1860'erne samt for kvinders stemmeret i 1910'erne.