The GTBS is the national sustainable tourism certification scheme for the UK & Ireland with over 2400 members. It is the only national certification programme endorsed by the National tourism agencies.

Businesses opting to join Green Tourism are assessed by a qualified grading advisor against a rigorous set of 145 criteria, covering a range of areas, including energy and water efficiency, waste management, purchasing, travel, biodiversity and more. Those businesses that meet the required standard, receive a Bronze, Silver, or Gold award based on their level of achievement. They are regraded once every two years.

The current network of members is comprised of a wide range of business types, including accommodation providers, visitor attractions, activity providers, conference and events venues, corporate offices and others.