Observations on a family group of four free-ranging Callicebus torquatus are reported for 235 hours on 18 complete days. Grooming sessions usually contained more than one grooming bout, and the longest grooming sessions occured on the sleeping bough, prior to dusk. On 12 days continuous observations were made on all grooming activity on the sleeping bough. The total time spent grooming, and the number and length of grooming bouts were recorded. Results suggest that grooming in C. torquatus is both a form of parental investment especially by the monogamous male, and a means of sustaining the male-female pair bond.