Impact evaluation is a methodological approach used in social sciences to measure the impact of a particular program, policy, intervention, or project on a specific outcome or target population. It involves assessing whether the intended goals of an intervention were achieved, as well as the overall effectiveness and efficiency of the intervention. Impact evaluation helps stakeholders make informed decisions about allocating resources and improving the design and implementation of future programs or policies. It typically involves the use of experimental or quasi-experimental methods, such as randomized controlled trials or difference-in-differences analysis, to determine causal relationships between interventions and outcomes.