Marketplaces are taking an increasing share of B2C online retail sales: Half of B2C online retail spend came from marketplaces in 2016. This report uses Forrester Data's Online Marketplace Tracker to examine 11 marketplaces across 16 countries to understand their share of the B2C eCommerce market and their growth trajectories from 2015 to 2017. This report also looks at the services and factors that will drive future adoption and growth for the key marketplaces.