Ever since Richard Titmuss published The Gift Relationship, it has been common to claim that donor compensation will undermine social cohesion. This chapter will provide a strong and novel argument for the view that allowing this would undermine social cohesion. This is not only important for the moral debate that concerns compensating the donors of blood or plasma. It is also important for debate over public policy in countries that currently prohibit donor compensation. Many countries (e.g., Canada) that prohibit donor compensation fail to procure a sufficient amount of plasma to meet the medical needs of their population. They thus import it to make up this shortfall – and do so from countries that they know allow donor compensation. A moral concern with social cohesion could justify treating domestic donors differently from foreign donors in this way. And it could do so without committing its proponents to the claim that social cohesion in their country (i.e., that which prohibits the compensation of domestic donors but allows the importation of plasma from compensated foreign donors) is more important than social cohesion in other countries (i.e., those that export their plasma). This chapter will outline and assess this proposed justification – and find it wanting.