The purpose of this paper is to review the trends and problems of previous research studies related to the determinants of assertive behavior. In earlier researches, the effects of various personality factors have been identified as determinants of assertive behavior.However, while these studies have provided investigations into factors such as irrational beliefs and self-esteem, there is a need to expand the research efforts. Currently, there is lack of investigations pertaining to the effects of the environmental factors, and the effects of the interaction between personality and environmental factors upon assertive behavior. These deficiencies have rendered previous inconclusive studies requiring further investigations. Therefore, this paper will advance the research effort by providing comprehensive perspectives of both the personality and environmental factors.