This study was an investigation of the effects of physiologically-oriented mental imagery on immune functioning. College students with normal medical histories were randomly selected to one of three groups. Subjects in Group 1 participated in short educational training on the production of secretory immunoglobulin A. They were then tested on salivary IgA, skin temperature and the Profile of Mood States (POMS) before and after listening to a 17-minute tape of imagery instructions with specially-composed background "entrainment" music, designed to enhance imagery. Subjects in Group 2 (placebo controls) listened to the same music but received no formal training on the immune system. Group 3 acted as a control and subjects were tested before and after 17 minutes of no activity. Treatment groups listened to their tapes at home on a bi-daily basis for six weeks. All groups were again tested at Weeks 3 and 6. Secretory IgA was analyzed using standard radial immuno-diffusion techniques. Repeated measures analyses of variance with planned orthogonal contrasts were used to evaluate the data. Significant overall increases (p < .05) were found between pre- and posttests for all three trials. Groups 1 and 2 combined (treatment groups) yielded significantly greater increases in slgA over Group 3 (control) for all three trials. Group 1 (imagery) was significantly higher than Group 2 (music) in antibody production for Trials 2 and 3. No group differences were noted in saliva volume or skin temperature, indicating that autonomic physiological mechanisms were not responsible for differences in antibody production. POMS changes more often favored Group 1. Symptomatology, recorded by subjects at weeks three and six, was significantly lower for three symptoms (rapid heartbeat, breathing difficulty, and jaw clenching), again favoring both treatment groups over the control group. Conclusions were that CNS-mediated immunoenhancement through mental imagery is possible.