The Building Engineering Services Association (formerly known as the HVCA) is the UK's leading trade organisation for building engineering services contractors – representing the interests of firms active in the design, installation, commissioning, maintenance, control and management of engineering systems and services in buildings. We offer three tiers of membership: BESA Membership - for companies and businesses of all sizes BESA Affiliate Membership - for manufacturers, suppliers and recruitment agencies for the BSE industry BESA Associate Membership - for individuals including apprentices, employees of BESA member companies, recently retired, consultants and more within the BSE industry.