The objective of this study was to measure the impact of stressors on personality types in Call Centers. Based on literature survey five potential workplace stressors were identified, namely (1) Task Demands, (2) Role Demands, (3) Interpersonal Demands, (4) Organizational Structure and (5) Organizational Leadership. Based on the literature survey, a relationship model was developed that was inclusive of the above stressors, and three personality types, which were Type A, Type AB and Type B.The sample size for the study was 100. The subjects were supervisors and agents drawn non-randomly from various Call Centers of Karachi. All the subjects completed a questionnaire comprised of 27 questions based on occupational stress index (Srivasta and Singh 1981) and AB Personality Continuum (National Institute of Safety and Health 1975). The three personality types A, B & AB all go through stress, however it is the Type A, which thrives on stress. The sources of stress measured in the study were Task Demand, Role Demand, Interpersonal Demands, Organizational Structure and Organizational Leadership.The stressor that most contributed to the Personality type A’s stress in the study was Interpersonal Demand (0.38), which is justified by the literature review as Personality type A are not team players and prefer to work alone.Whereas Personality type B was stressed because of Role Demand (0.38) which is also proved by the literature review as personality type B are laid back and do not take there roles seriously. Hence it can be concluded that it type A tends to cope well with stress as compared to type AB and type B. The performance of the respondents can be made better if the supervisors are aware of the personality types and thereby motivate them according.