The review has five objectives. The first objective is to operationalize the inputs (neighborhood watch) and the outcomes (crime) for the purpose of conducting the review. The second objective is to identify studies that have evaluated the effect of neighborhood watch on crime. The third objective is to identify a list of studies that meets the minimum criteria of scientific rigor. The fourth objective is to obtain a comparable measure of effect size in the selected most rigorous studies. And the final objective is to arrive at a conclusion about the effectiveness of neighborhood watch. The following types of intervention to be included in this review are stand-alone neighborhood watch schemes; neighborhood watch schemes that include property marking and security surveys; neighborhood watch schemes that include a watch component; and comprehensive programs that include neighborhood watch and other unrelated schemes. One of the most important defining elements of neighborhood watch is the mechanism by which the project aims to reduce crime. The main mechanisms of the “watch” part of neighborhood watch schemes are residents operating as the "eyes and ears" of the police, looking out for suspicious behavior, reporting suspicious behavior to the police, and interacting and working together to solve problems. The types of crimes to be covered in the review are crimes against residents, dwellings, other street crimes occurring in the watch area, and disorder in the area. The criteria for selecting rigorous evaluations will be based on the Maryland Scientific Methods Scale, a five-point scale measuring overall internal validity. The principal reviewer in collaboration with the other reviewers would update the review once every 2 years. 14 references