It has been suggested that a unique feature of some mental heath practitioners' work is exposure through their role as therapists to clients' descriptions of and reactions to trauma, and that these experiences may actually indirectly cause distress and traumatization to the therapist. This proposed phenomenon has been termed "vicarious traumatization" (VT) and is the focus of the current review. The concept of VT, together with other related concepts such as "burnout," "compassion fatigue," "secondary traumatic stress" (STS), and "work stress" are appraised. Psychological mechanisms that might be theoretically involved in VT are considered. The measurement of VT is reviewed alongside the limited research evidence supporting its existence. Factors such as direct trauma exposure and the personal attributes of mental health workers, which have been suggested to be associated with VT, are also assessed. It is concluded that the evidence to support the existence of VT is meager and inconsistent. Future research needs to be directed at distinguishing VT from other sources of distress arising within the workplace. Finally, the organizational relevance of VT and its possible implications for the management of mental health workers are critically appraised.