Depending on your back yard area, anywhere from 18″ to 36″ away from the inside edge of the pool. Preferably between 30″ to 36″ because you will need at least 24″ to get out of the pool. The fence must be installed either as a “closed-loop” (with all mesh fence sections connected to one another using the spring-loaded safety latches), or the two ends of the fence must be securely fastened to a wall or similar structure.