This study examines stress perceived by telephone intervention volunteers at a suicide prevention center before their shift, during the most high-urgency call, and after the shift. Eighty of the 82 active volunteers completed questionnaires concerning stress, coping strategies, motivations for volunteer work, and experiences with suicide. Stepwise multiple regression analysis indicated that only one variable, the amount of experience in telephone intervention with suicidal persons, predicted stress level before the shift; volunteers with more experience tended to be less stressed. Stress during the most urgent call was related first to the level of urgency of the call, then to the total length of all calls received, followed by the coping mechanisms of magical thinking, detachment, and feeling personally responsible. Stress after the shift was related first to the total amount of time spent on calls, then to the number of other persons present during the shift. Stress after the shift was also negatively related to amount of education and having realistic expectations about interventions. Magical thinking was positively related to stress, and the mechanism of positive thinking was negatively related. A high proportion of volunteers had attempted suicide, had previous thoughts about suicide, and had known persons who attempted or died by suicide. These findings are discussed as to their implications for the selection and training of volunteers in suicide prevention.