Multi-level marketing (MLM) is a marketing strategy in which the sales force is compensated not only for sales they personally generate, but also for the sales of the other salespeople that they recruit. This recruited sales force is referred to as the participant's downline, and can provide multiple levels of compensation.

MLM companies have been a frequent subject of criticism as well as the target of lawsuits. Criticism has focused on their similarity to illegal pyramid schemes, price fixing of products, high initial start-up costs, emphasis on recruitment of lower-tiered salespeople over actual sales, encouraging if not requiring salespeople to purchase and use the company's products, potential exploitation of personal relationships which are used as new sales and recruiting targets, complex and sometimes exaggerated compensation schemes, and cult-like techniques which some groups use to enhance their members' enthusiasm and devotion.