The primary purpose of this report is to standardize problem gambling prevalence rates so as to facilitate comparisons between jurisdictions as well as within the same jurisdiction over time. The first step in this process was the identification and collection of all published and unpublished studies that involve a jurisdiction-wide adult prevalence survey of problem gambling. The second step in this process was the examination of the impact of methodological differences on obtained problem gambling prevalence rates. The third part of this report presents the results of applying weighted factors to create standardized past year problem gambling prevalence rates for all studies. Considering that gambling availability has steadily increased in most jurisdictions over the past 30 years, the results support that increased gambling availability is related to increased problem gambling, and that populations tend to adapt over time.