To date, building energy management systems (BEMS) have been well established in the large scale non-domestic field as an energy saving technology, contributing towards sustainable future cities. They utilise complex control interfaces, with control signals passed through purpose built communication wiring. Estimated end-use energy savings, due to BEMS addition, can reach up to 50%, with associated financial savings for building users. The intelligent control, featured in BEMS, enables buildings to adapt; optimising operation based on weather forecast data. Traditionally they have been complex to install and operate, requiring trained personnel to maintain. Alternatively domestic BEMS are growing in popularity, monitoring and controlling the simple heating functions of a house. This work outlines the development of a novel BEMS for the small to medium sized non-domestic market. The market features a variety of building types, sizes and uses therefore an adaptable and intuitive system is required to facilitate energy savings within the sector. From initial concept, through a brief review of the market, this work finally presents a viable BEMS to reduce end-use energy in non-domestic buildings. Having showcased the development of an intuitive monitoring GUI, the energy saving results from a single-occupancy office trial found PIR control more beneficial than daylight illuminance threshold control, for the office trial context. Combining the two control methods achieved 67% savings during the test period.