There are certain professions (law and medicine for example) where there rules restricting how you can partner with others, who can you partner with, and whether you can pay for "leads" or client referrals. If you are not in an industry with such rules, you can do any of the following: 1) employ him as an employee and pay him as one (e.g. low base wage with a commission or bonus for clients); 2) make him a partner in your business with the arrangement that his compensation is solely in the form of a payment for clients or a share of the proceeds from clients he brings in; or 3) have him as an outside/independent contractor who is paid an agreed-upon amount (either a set fee or commission/percentage) on work he brings in. Any of these would be legal; for what you suggest, 3) would be best, since it pays him for the one thing he's supposed to do while otherwise minimizing his connection to your business; it would be the easiest structure to change, modify, or discontinue. Just put the terms of the agreement in writing (e.g. what he has to do to get paid, how much he is paid, when he is paid, etc.) and be sure to include a clause allowing you to terminate the arrangment on notice (e.g. 30-day notice).