Problem gambling prevention consists of a range of initiatives, each intended to reduce potential harm caused by legalized gambling. The traditional way of categorizing prevention efforts is by the type of people the efforts are directed toward. Primary Prevention is an effort to prevent individuals in the general populace from becoming problem gamblers. Secondary Prevention is an effort to prevent the development of problem gambling in individuals with risk factors for the condition. Tertiary Prevention is an effort to stop and potentially reverse the problems occurring in existing problem gamblers. However, another approach, and the one used in the present paper, is according to the nature of the initiative. Virtually all prevention initiatives can be categorized into two groups. Educational Initiatives are intended to change internal knowledge, attitudes, beliefs, and skills so as to deter an individual from problem gambling. Policy Initiatives are intended to prevent problem gambling through the alteration of external environmental controls on the availability and provision of gambling. The purpose of this paper is to comprehensively review what is known about the nature and effectiveness of educational and policy initiatives to prevent problem gambling.