the catalyst database, which is operated through the ontario centre for addiction and mental health, was used to explore factors that may be related to treatment non- compliance and the number of admissions in the population of clients receiving addiction treatment in thunder bay between 2003 and mid-2006. the distinction between primary and secondary gamblers identified by nguyen (2007) was explored to determine whether this distinction is useful in predicting if the two groups differ in treatment non- compliance and the number of admissions. a total of 2,743 clients were examined. comparisons were made between those who presented for treatment of gambling as their primary problem (n = 138), those who presented for a substance addiction (n = 280) with gambling as a secondary problem, and those who had only a substance addiction (n = 2,178). non-compliant individuals are more likely to be gambling clients, younger, female, have a higher education level, better income source, better employment, and no legal problems. an individual with more admissions to treatment is more likely to be a secondary gambler or substance problem only client, older, have a poorer source of employment and have legal problems. the distinction between primary and secondary gamblers was not found to be useful for predicting treatment non-compliance but did predict the number of admissions. it appears that these two outcome variables are measuring different aspects of treatment utilization and that it is important to consider each separately, as they both provide useful program planning information.