Building services engineering (BSE) is a professional engineering discipline that strives to achieve a safe and comfortable indoor environment whilst minimizing the environmental impact of a building.

Alternative titles are "mechanical, electrical and plumbing" (MEP) engineering, "technical building services", "building engineering" or "facilities and services planning engineering". The term BSE is widely used in Commonwealth countries (incl. United Kingdom, Ireland, Canada and Australia), but in the United States of America, Asian countries Saudi Arabia and Pakistan, the MEP engineers are known as "services planners".

In some countries, a "building services engineer" is a Senior MEP engineer with experience in the installation of equipment in Buildings Construction, Building Maintenance, Management, integration of electrical, mechanical, fire, hydraulic, security and communications building services, who manages and delivers the integrated detailed design of multiple disciplines so as to ensure that the building is delivered in a "least cost technically acceptable" manner, with emphasis on both the construction costs and the operational costs.