Thirty-nine percent of the agencies with a negotiator use a mental health professional consultant to the negotiation team. Police agencies that use a mental health professional as a consultant on negotiation techniques reported more hostage incidents ending by negotiated surrender and fewer hostage incidents ending by tactical team assault and arrest of the perpetrator. Also, police agencies that use a mental health professional as a consultant on the assessment of the perpetrator reported fewer hostage incidents resulting in the serious injury or death of a hostage. Although these results are only correlational, they raise the possibility that the use of mental health professionals as consultants to police hostage negotiation teams may decrease the risk of hostage injury and death. 4 tables and 11 references