It is interesting to point out that there have been fewer applications of the mixed methods triangulation strategy in outcome evaluation than in process evaluation. One of the major reasons is the costs involved. For example, it is already highly expensive to apply a quantitative method such as a randomized experiment in an outcome evaluation for a program such as providing HIV prevention services to injection drug users. The application of the mixed methods triangulation strategy would mean sending a group of qualitative evaluators into the field for a long time to engage in a prolonged investigation of the effect of the program. The qualitative outcome evaluation could easily be as costly as the quantitative outcome evaluation. The application of the mixed methods triangulation in outcome evaluation could easily double the price of an evaluation in comparison to the use of a single method. This additional cost is a huge barrier for funding agencies and other decision-makers who are deciding if they want to support an outcome evaluation that uses the triangulation strategy. This barrier would be more easily overcome if there were more evidence available to use in convincing funding agencies that the