Homeless individuals who are dually diagnosed have generally received poor services in treatment programs. Either the programs do not integrate mental health treatment with substance abuse treatment or the integrated programs have been too rigid to address complex dual diagnosis issues. Recently, flexible and integrated treatment programs have started to crop up to address this service gap. However, these programs often lack comprehensive evaluation data. Drawing on research with a stages of change, integrated treatment program, I explore potential ways to evaluate the short- and long-term outcomes of similar programs. The development and implementation of a comprehensive evaluation strategy is an important step to assessing the value of flexible and integrated dual diagnosis treatment programs.