The issuing of defensive spray -- specifically oleoresin capsicum (OC) spray -- to police was a recommendation of the Queensland Police Service Project Lighthouse report (1996) and follows similar moves by interstate police services. OC spray is intended to give police an additional tool for use in resolving threatening, dangerous incidents. A joint Queensland Police Service-Criminal Justice Commission Steering Committee was appointed in October 1997 to implement the trial; evaluate the trial, including the OC spray product; and make recommendations as to the future use of OC by the Queensland Police Service. The Steering Committee set the following criteria by which to judge the results of the trial: the spray's effectiveness; whether the spray was used appropriately; the number of injuries/deaths caused or avoided by use of the spray; and the impact on complaints against police. During the trial there were 35 incidents that involved OC spray, all but one occurring during the second 6-month phase of the trial. Seven of the incidents involved attacking dogs. In the 28 incidents involving human attackers, there were 37 deployments (discharges) of OC by an officer against a subject and 3 recorded uses in which the spray was presented to the subject but not discharged. The overall conclusion of the Steering Committee was that the aims of the trial were generally met. There were no serious problems with the use of OC spray during the trial, and there were strong indications that OC spray would prove a useful addition to the current range of incident resolution options available to Queensland police officers. Four recommendations are offered for the implementation of police use of OC spray. 25 references and appended trial evaluation forms and data tables