Another organization that clearly makes this distinction is the NGO Global Alliance Against Traffic in Women. Their report "Trafficking: A Demand Led Problem?" is excellent overview of the multifaceted nature of the sex industry and the relationship of sex trafficking to parts of that industry.

The positions of GAATW are, naturally, opposed by the abolitionist NGO Coalition Against Trafficking in Women, which has managed to get them largely cut off from any US-based government funding based on their non-abolitionist stance on prostitution. The Mother Jones article Sex Trafficking: Zero Tolerance" gives more info about this.

One of the member groups of the GAATW, the La Strada Association, is one of the main groups doing actual work on the ground in Eastern Europe trying to help trafficked women there.