The illicit markets of prostitution and sex trafficking are, like any other markets, driven by demand. Wherever demand occurs, supply and distribution emerge. While it may be an oversimplification to say that demand is the sole cause or influence on markets, and that there are feedback mechanisms and interactions among these three main components, it is indisputable that removing or reducing demand reduces or eliminates markets. The need for people to provide a “supply” and for pimps and traffickers to “distribute” the supply to buyers would not exist without demand. The historic emphasis on interfering with supply and distribution systems has been ineffective at producing substantial and lasting reductions in illegal commercial sex markets. Given that people are the commodity exploited, supply is difficult to contain. Distribution is also difficult to contain: since the markets are highly profitable, arrested traffickers and pimps are soon replaced. Distribution requires relatively little skill, and supply is plentiful and easily acquired, presenting few barriers to entry or startup costs for pimps and traffickers.
Demand Reduction is Primary Prevention. Primary prevention refers to stopping negative events before they occur, ensuring that people do not become afflicted rather than addressing the symptoms of the afflictions that have occurred. The majority of effort to confront prostitution and sex trafficking in the United States has been devoted to tertiary or secondary approaches (trying to stem the progression of a problem, or recover from an affliction after it has occurred); while relatively little investment has been made in primary prevention (attacking consumer-level demand).
-U.S. Department of Justice 2012