The purpose of this study was to investigate the hypothesis that there would be significant differences in selected personality traits between volunteers and nonvolunteers for a crisis intervention center, a 24-hour emergency telephone service. Volunteers for the center were required to complete a 32-hour training program to qualify for service in the center; a portion of the original volunteer population, however, did not complete the program. The final comparison, therefore, was made between the following three groups: (1) a group of volunteers who completed the required training program for a crisis intervention center, (2) a group of volunteers who did not complete the required training program for the center, and (3) a comparable group of non-volunteers.The five personality variables that were selected for measurement were ascendancy, responsibility, emotional stability, sociability, and dogmatism as measured by Gordon Personal Profile and Rokeach Dogmatism Scale. The selection of the traits was prompted by a review of literature which indicated that the traits were associated with the characteristics of effective counselors, with the intent of implementing the inevitable comparison that will be made between talents of volunteers and the requirements for effective service.A total of 179 subjects participated in the study. In order to validate comparisons that were made between volunteers and non-volunteers, the volunteer sample, the total group of persons attending the initial session of the training, was stratified into male:female and student: non-student groups before the non-volunteer population was selected. Established groups were then met by the examiner, tested, and invited to volunteer for the crisis center; data from those declining the invitation to serve were used to form the non-volunteers.Three statistical procedures were used to test the hypotheses: a one way analysis of variance, an analysis of covariance, and Scheffe's method of comparing means following a significant F test. Of the four null hypotheses, all were rejected. Review of the data led to the following conclusions:(1) Volunteers for a crisis center were more ascendant, more responsible, more emotionally stable and less dogmatic than those who chose not to volunteer.(2) Volunteers who completed the training program and volunteers who did not complete were alike on every trait except emotional stability. Completing volunteers were most stable.(3) A large part of the observed variances were accounted for by the female population. Female volunteers differed significantly from female non-volunteers on ascendancy, responsibility, emotional stability and dogmatism. Male volunteers differed from male non-volunteers only on the trait of dogmatism.(4) Volunteers for a crisis center exhibited the characteristics associated with effective counselors to a more significant degree than did the non-volunteers. These characteristics included open-mindedness, responsibility, stability, and flexibility.Implications were drawn concerning the use of volunteers in mental health programs on the basis of self-selection in conjunction with a short, intense training program. Recommendations were made for further research to determine similarities in other volunteer groups for other mental health projects, to investigate further the wide variances observed in the female population, and to more clearly define effectiveness for mental health roles.