Safety

Never leave a child unsupervised near a pool.
Instruct babysitters about potential hazards to young children in and around swimming pools and the need for constant supervision.
Completely fence the pool. Install self-closing and self-latching gates. Position latches out of reach of young children. Keep all doors and windows leading to the pool area secure to prevent small children from getting to the pool. Effective barriers and locks are necessary preventive measures, but there is no substitute for supervision.

Do not consider young children "drown proof" because they have had swimming lessons; young children should always be watched carefully while swimming. See Infant Swimming Resource for a good swimming to help prevent drowning of young children.
Do not use flotation devices as a substitute for supervision.
Never use a pool with its pool cover partially in place, since children may become entrapped under it. Remove the cover completely.
Place tables and chairs well away from the pool fence to prevent children from climbing into the pool area.
Keep toys away from the pool area because a young child playing with the toys could accidentally fall in the water.
Remove steps to above ground pools when not in use.
Have a telephone at poolside to avoid having to leave children unattended in or near the pool to answer a telephone elsewhere. Keep emergency numbers at the poolside telephone.
Learn CPR (cardiopulmonary resuscitation).
Keep rescue equipment by the pool.