The trust has its headquarters at Woods Mill near Small Dole and has 30,000 members including junior members. The Woods Mill site is itself a nature reserve with a lake, woodland and meadows.
The Trust manages over 3000 acres (12 km²) of downland, woodland, wetland and heath. Their work also includes environmental education, working with land owners, companies and local communities to conserve Sussex. The trust also manages many projects across the county of Sussex including the Sussex Otters and Rivers project.