This grant provides 40 months of continued funding for the MSRI Undergraduate Program (MSRI-UP) at the Mathematical Sciences Research Institute. The MSRI-UP program includes (1) an annual six-week summer research experience for 18 undergraduate mathematics students from underrepresented groups working in research teams of three, (2) colloquia and professional development workshops, (3) presentations at national math conferences following the summer program, (4) an introduction to a wide community of peers and mentors, and (5) long-term follow-up and mentorship. The research efforts of participants will result in technical reports posted on MSRI’s website, oral presentations at a culminating symposium, and presentations at various national conferences. Of former MSRI-UP participants with bachelor’s degrees, 82% have continued into graduate programs, including 70% in doctoral programs. Though the program was only started in 2007, 45 alumni have gone on to earn MS degrees and 20 have completed PhDs. These achievements are especially noteworthy given the program’s focus on recruiting underserved students who are not clearly headed for a graduate program in mathematics and who are not high GPA students from elite high schools.