This document discusses whether an SSP (supply side platform) should buy a DMP (data management platform). It provides an overview of the digital advertising value chain and the growing market for DMPs. The key components of a DMP platform are described, and different DMP players in the market are classified. A breakeven analysis is presented showing that buying a DMP could provide returns within a year if data usage is over 5%. Both pros and cons of buying a DMP for an SSP are discussed. The recommendation is that buying a DMP would accelerate time to market but the SSP would still need partnerships with other data providers.