The book explores the critical importance of impact evaluation in modern program management, demonstrating how proper evaluation methods can lead to better decision-making and more effective resource allocation. It emphasizes that understanding 'why evaluate' is crucial for building sustainable and effective programs.

The text presents a structured approach to evaluation design, covering various methodologies from randomized control trials to quasi-experimental designs. It provides practical guidance on selecting the most appropriate evaluation method based on program context, resources, and objectives.

Detailed attention is given to the operational aspects of conducting impact evaluations, including planning, data collection, analysis, and reporting. The book emphasizes practical considerations and real-world challenges that practitioners might face during implementation.