Objectives: To determine the prevalence of pathologic gambling among substance-related disorder patients admitted at The Medical City Psychiatric Unit and describe the demographic characteristics of identified pathologic gamblers. Methods: Patients admitted under the pyschiatry service of The Medical City from June 2003 to March 2004 who fulfilled the DSM-IV TR diagnostic criteria for Substance-Related disorders were included in this study. The South Oaks Gambling Screen (SOGS), a validated and reliable instrument for screening populations with gambling problems was administered to determine the presence of pathologic gambling. Demographic data was also collected from patients. Results: Fifty one patients were eligible for the study but only 49 participated in the study since 2 did not give their consent. Eleven patients (22.45%) were identified as probable pathologic gamblers (PPG) and 21 patients (42.86%) were considered problem gamblers (PG). Majority of the PPG were male, ?40 years of age, received some college education, abused methamphetamine, and had a family history of gambling problems. Conclusion: There was a high prevalence of pathologic gambling among patients with substance-related disorders. Thus, it is recommended that assessment of gambling problems should be part of the initial psychiatric evaluation of substance-related disorder patients. Further local research on this topic should also be conducted to validate results of this study.