Placing into perspective the meaning of evidence for evaluation professionals and applied researchers, the contributors to this book--a veritable "who's who" in evaluation--provide observations about the diversity and changing nature of credible evidence. The editors include lessons from their own applied research and evaluation and suggest ways in which practitioners might address the key issues and challenges of collecting credible evidence. The Second Edition offers updated thoughts on each chapter's topic, as well as two new chapters that address assessing credibility and implications on...