In Forrester's 53-criteria evaluation of demand-side platform (DSP) vendors, we identified the nine most significant software providers — AOL, AppNexus, AudienceScience, DataXu, Google, MediaMath, Rocket Fuel, The Trade Desk, and Turn — in the category and researched, analyzed, and scored them. This report details our findings about how well each vendor fulfills our criteria and where they stand in relation to each other to help B2C marketers select the right partners for their demand-side platforms.