Staying abreast of the most recent developments in research is becoming an ever more challenging task. The sheer volume of evidence available is growing each year. Therefore, identifying the studies most relevant to a specific topic or question can be difficult (Snilstveit et al. 2016).1 Most evaluators have only a limited amount of time and resources to engage critically with research. Urgency to implement projects or make decisions about policies often amplifies this problem.

A literature review can help address such issues by surveying existing research on a given topic. Surveys of this type may serve several purposes, such as providing an overview of current understanding related to a particular issue, appraising the relevance of existing theories and evidence, providing information to form the basis of future interventions (or improve existing ones), and guiding future research (Petticrew and Roberts 2005). However, literature reviews also have well-documented limitations. A literature review may not be comprehensive, and its authors may be unbalanced in their selection of literature to discuss. Authors may cherry-pick evidence favorable to their own opinions or vested interests, raising questions about the reliability and validity of their findings (Snyder 2019; White and Waddington 2012).

Scientific understanding of systematic procedures for producing reviews of evidence has improved over the past decade, and use of such procedures has increased (Waddington et al. 2012; Waddington, Masset, and Jimenez 2018). Reviews of this type aim to minimize bias by ensuring transparency in experts’ efforts to identify relevant research and report their findings (Higgins et al. 2019). Along these lines, the Independent Evaluation Group is also promoting more rigorous standards for reporting existing evidence in its evaluations, mainly by encouraging the use of structured literature reviews. Its guide to evaluation methods notes that a structured literature review is intended to determine a given topic’s state of the art using systematic and transparent procedures for synthesizing existing evidence (Vaessen, Lemire, and Befani 2020). This paper provides an overview of various concepts and methods that researchers can use to systematically summarize evidence from a large collection of literature. This is supported by a case study using a literature review to summarize evidence related to an evaluation of the World Bank’s Doing Business project.

Chapter 1 looks at various literature review methodologies, defining them according to their scope and the practical considerations required to implement them. Chapter 2 shows how to apply the approach, using the recent Independent Evaluation Group evaluation of the World Bank’s Doing Business project as a case study. Chapter 3 concludes with closing remarks and practical reflections on the approach.