The Mathematical Sciences Research Institute Undergraduate Program (MSRI-UP) at the Simons Laufer Mathematical Sciences Institute (SLMath, formerly MSRI) is a comprehensive six-week summer program for undergraduate students who demonstrate exceptional potential for and interest in pursuing graduate studies in mathematics. The goal is to identify talented students, especially those from underrepresented groups, and make available to them meaningful research opportunities and a community of academic peers and mentors. Each year, MSRI-UP invites 18 students to the UC Berkeley campus, where their academic curriculum consists of two weeks of structured coursework followed by four weeks of supervised, group research. Additionally, students attend workshops on applying for and succeeding in graduate school, including career conversations with professional mathematicians. Weekly research colloquia feature a variety of mathematical topics and applications. At the end of the summer, students produce formal reports and give oral presentations on their research to their cohort and invited guests. MSRI-UP programming continues throughout the following year, focused on how to present work at research conferences, submit articles for publication, and eventually apply for graduate school.