E&M may stand for:
E and M signaling, a type of supervisory line signaling that uses DC signals on separate leads Encrypt-and-MAC (E&M), an approach to authenticated encryption Electromagnetism, sometimes also called electricity and magnetism, a branch of physics Electromechanics, combines electrical engineering and mechanical engineering Evaluation and Management Coding, a medical billing process in the United States Exchange and Mart, a defunct long-established British sales publication AP Physics C: Electricity and Magnetism, also known as AP E&M, an advanced placement course Mechatronics, a portmanteau of electronics and mechanics