Also known as a Taft-Hartley plan. An employee benefit plan maintained in accordance with a collective bargaining agreement between a labor union and more than one employer. Multiemployer plans typically cover unionized employees that work for several different employers within the same industry. The plan is jointly administered by representatives from both the contributing employers and the labor union (29 U.S.C. § 1002(37)). A multiemployer plan can be a multiemployer pension plan or a multiemployer welfare benefit plan.

Under the Multiemployer Pension Plan Amendments Act of 1980, a multiemployer plan must be maintained for a "substantial business purpose" (29 C.F.R. § 2510.3-37). Multiemployer plans must satisfy other requirements as the Secretary of Labor prescribes by regulation.