We present a Macintosh-based computer system for collection and analysis of rodent sexual behavior. Two computer programs are presented. The first is an entirely generalizable real time data collection program that records any keyboard or keypad inputs (e.g., user defined behavior codes) and their time of occurrence. The second is somewhat generalizable; we use it to analyze frequencies, durations, and latencies relative to a copulatory series (including mounts, intromissions, and ejaculations). To our knowledge, these are the first such programs available on the Macintosh platform.