HCSSiM is an intensive six-week encounter with college-level mathematics for talented and highly motivated high school students. The daily schedule includes 4 hours of morning classes (Mon-Sat), the pre-supper Prime Time Theorem, and evening problem sessions. Afternoons are devoted to reading, rest, recreation, occasional trips to town, and informal study. Participants have unparalleled access to faculty members in classrooms, at meals, and in the program dorm. Productive collaborations continue long after the program, and many lifelong friendships are forged. The 45th session of the Hampshire College Summer Studies in Mathematics will happen July 2 - August 12, 2017. Applying is fast, free, fun, obligationless, and doable on line (hcssim.org) even while other options are being explored. Not applying unnecessarily closes doors, means not seeing the 2017 Interesting Test, and may cause drowsiness and boredom.