Systems and methods for real-time interactive wagering on event outcomes are presented. Clients are first qualified and given wagering limits before being allowed to interactively wager on event outcomes. Event outcomes may be based on, for example, financial markets and indices, sporting and entertainment events, casino performances, and natural phenomena such as weather and earthquakes. Events on which wagers can be placed include both those with known and unknown outcome probabilities, and wagers can be a fixed-odds type or a spread-bet type. Wager transactions, including acceptances and confirmations, are executed in real time. Clients can customize displays of events on which they are authorized to wager. Real-time client credit management, automatic dealer hedging, automatic price-spread adjustments, and automatic client and dealer defined wagering limits are also provided.