Multi-level marketing (MLM) is a marketing strategy in which the sales force is compensated not only for sales they 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. Other terms used for MLM include pyramid selling, network marketing, and referral marketing. According to the US FTC, some MLM companies constitute illegal pyramid schemes which exploit members of the organization.