Over the last years, several comprehensive training programs for problem gambling have been developed and implemented in various casinos around the world. However, the efficacy of these programs has rarely been assessed and evaluated scientifically. A workshop called "Des gens qui font la difference" (People Making a Difference) was developed to train casino employees about problem gambling and how to offer help to gamblers in crisis. Two thousand four hundred and thirty-two (2,432) employees of the three casinos in the province of Quebec, Canada were enrolled in these training sessions. The employees completed a self-administered questionnaire at the beginning and at the end of the session, and were also invited to participate in a 6-month follow-up. One-thousand six-hundred fifteen (1,615) employees of the three casinos agreed to be contacted by phone for the follow-up. Of this number, 789 answered the questionnaire, which constitutes a participation rate of 32%. The results showed that participants demonstrated a better understanding of the notions of chance and randomness, and of problem gambling. They were more convinced of their role in identifying gamblers in crisis and displayed a greater knowledge of the procedure that has been implemented to help gamblers. At the follow-up, results indicated that participants maintained a good understanding of the notion of randomness and remained convinced about the importance of receiving information about available help and resources. However, some notions about problem gambling and the procedure implemented to help gamblers in crisis were not well maintained. In conclusion, the awareness training session on responsible gambling allowed employees to increase their knowledge about gambling and improve their attitudes regarding gamblers. Since some important components that were taught--such as the established procedure to help gamblers--were not well assimilated, awareness training program planners in casinos need to schedule for additional information to be made available (refresher courses, posters, brochures, videos) to keep employees well informed.