Despite clear evidence of the benefits of taking advanced math courses in high school, access to and success in these courses are not experienced equally. Only about half of California high school seniors enroll in an advanced math course, and nearly one-quarter of seniors do not take any math. To increase equitable access to advanced math, six partnerships between university faculty and high school math specialists have developed advanced innovative math (AIM) courses as viable alternatives to traditional 12th-grade math courses. This report highlights the ways in which these partnerships demonstrate and benefit from the common features of successful intersegmental partnerships including: (1) investment of state resources; (2) shared purpose; (3) commitment to equity; (4) community building; (5) capacity development; and (6) improved educational outcomes.