Working conditions for employees in the transport sector might present an opportunity structure for gambling by providing access to gambling during the workday. This study investigates connections between opportunity structure, gambling during the workday, and gambling problems among employees in the transport sector. Data has been collected from three different transport organizations in Norway: bus, truck, and taxi drivers (N = 1033). 6.8% of the sample gambled during working hours and 3.2% of the employees could be characterized as having a gambling problem. We found a positive relationship between opportunities to gamble during working hours and problem gambling, with the odds for problem gambling increasing fourteen-fold if employees gambled during working hours. Gambling during the workday is a major risk factor for gambling problems in this sample.