Conducting effective process and outcome evaluations requires correctly identifying dependent and independent variables, and applying the appropriate methodologies. A major issue in process evaluation is ensuring both the strength and the integrity of the treatment. In outcome research, the rigor of designs is a major issue. Owing to practical and ethical limitations, application of the experimental method is likely to be difficult or impossible in many cases. Consequently, researchers may be forced to rely on quasi-experimental methods such as nonequivalent control group designs, time-series analysis, causal modeling, power analyses, and regression discontinuity designs in an attempt to achieve causal and plausible results. 73 references.