The relationship between Pareto optimal (@Q"s) and revenue maximizing (@Q"r) tolls is examined for queuing models that permit balking. When customers have the same value for waiting time, @Q"s @? @Q"r provided the entrepreneur can impose a simple two-part tariff. With heterogeneous values for waiting time, @Q"r can be greater than, equal to, or less than @Q"s. Expanding the number of servers and charging multi-part tariffs are shown to be alternative methods for segmenting the market, and the welfare implications of these two strategies are explored.