One large social group of each of three species of macaques (Macaca mulatta, M. fascicularis, M. radiata), housed in half-acre field cages at the California Primate Research Center, were observed for a total of 150 h. Data on sexual behavior and dominance interactions were recorded by pairs of experienced observers using a focal animal technique. Single or multiple mount-to-ejaculation sequences, number of thrusts per mount, number of mounts per sequence, duration of mounts per sequence, duration of sequences, social rank and frequency of sexual activity were recorded for each adult male. M. mulatta used a multiple mount-to-ejaculation (MME) pattern in 91% of their copulations. M. radiata used a single mount-to-ejaculation (SME) pattern in 91% of their copulations. M. fascicularis used both patterns—53% MME and 47% SME. A positive correlation was found between rank and sexual activity in fascicularis and mulatta males. A negative correlation between rank and sexual activity was found in radiata males and also a positive correlation between rank and age indicating that the youngest and most subordinate radiata males were the most sexually active males. In reviewing the literature, a relationship between degree of intermale competition, intermale tolerance and type of mounting pattern was revealed. Macaque species that primarily use an SME pattern also show sa high degree of intermale tolerance and little interrnale competition. Macaque species that primarily use an MME pattern typically show a high degree of intermale competition and a low degree of intermale tolerance. Possible events leading to such relationships are discussed.