To help inform the design and review of alternative public regulatory policies towards paid adult sex markets, this study uses economic reasoning to explore the nature of client participation. This is a timely focus given the increasing consideration and movement towards a greater role for demand-side policies and regulation that has emerged in some countries to complement, or, in some cases, even replace elements of supply-side regulation and policy. The analysis is based upon a time allocation model that characterises the nature and balance of incentives facing clients under various public regulatory regimes. The regimes considered range from the status quo in England, Wales and Scotland, to varying levels of state involvement or direction, featuring, inter alia, supplier registration, public health inspections and locational restrictions. All of these are shown to affect in various ways the extent to which risk, income and other factors can influence the pattern and intensity of leisure time usage, which is a key requirement for client participation in paid sex markets.