A Practice Note providing a general overview of multiple employer retirement plans (MEPs). The Note explains the rules governing MEPs under the Employee Retirement Income Security Act of 1974 (ERISA) and the Internal Revenue Code (Code), including the final Department of Labor (DOL) regulations on the definition of "employer" under ERISA § 3(5). The Note addresses the changes to MEPs under the SECURE Act, including pooled employer plans and relief for the bad apple qualification problem.