Objective: During January 2016-June 2017, 75 mumps outbreaks occurred in US universities, despite high vaccine coverage among students. We evaluated universities' experiences with mumps outbreaks to inform policy deliberations on use of a third dose of MMR vaccine and CDC guidance. Participants: American College Health Association members in September 2017. Methods: Online survey assessing mumps outbreak characteristics and response measures distributed to 980 members. Results: Administrators from 251 (26%) universities from 47 states responded. Seventy-nine (31%) universities had mumps cases on campus during August 2014-August 2017; 17 (22%) recommended a third MMR dose. The main challenges reported in outbreak response were exclusion of persons without presumptive immunity and isolation of students with mumps. Universities' advice on addressing challenges is described. Conclusion: We identified common challenges faced by universities during mumps outbreaks, and lessons learned. These findings informed the October 2017 recommendation for use of a third MMR dose.