The study aims to verify the relationship between leaders' personality traits in leader - member exchange (LMX), and job performance. Hierarchical Regression Analysis was used to examines (a) how leaders' personality traits and LMX affect the influence of social capital on job performance and organizational citizenship behavior; (b) how perceived organization support (POS) can moderate the influences of LMX on social capital, in turn impacting job performance and OCB. Responses are employees in the service industry in Thailand, which consisted of 236 independent samples in 77 groups. Each grou...