Due to recent changes of gambling laws, accessibility to gambling has become more widespread and thus, there has also been an increase in the prevalence of pathological gambling (PG). The wide range of social, economic, and psychological problems associated with PG are well known. There is a need for better understanding of PG and this review attempts to do so. Literature searches using the Medline and PsycINFO databases were used. Critical examining of the literature showed that familial/genetic, sociological, and individual factors (e.g., an individual's personality, biochemistry, psychological states, and cognitions) are implicated in the development and maintenance of PG, yet at present, the evidences are not solid. Similarly, there have been a lot of theories for PG but again, none of them are solid enough to provide a clear understanding of PG. Recent psychological-based theories seem to provide some solid ground for further research. We highlight four areas for future consideration for research. (1) Most studies have generalized findings from one form of gambling to another. It is suggested that it is now not tenable to consider gambling as a single phenomenon that can explain all forms of gambling. (2) Almost all of the studies in the gambling literature are Western-based and the results are often generalized to other ethnic and cultural groups. There is now an urgent need to close this gap. (3) Future studies need to address methodological problems in the current gambling/PG literature. (4) Almost all of the gambling literature has focused on the issue of why people start gambling. It is suggested that looking at variables as to why people stop gambling in a single episode may be a more fruitful area of research then why people start gambling. This is because what motivates one to continue gambling, despite losses in a session and across sessions, is a characteristic that distinguishes nonproblem gamblers from problem gamblers and pathological gamblers (PGs).