Strabismus is a failure of the two eyes to maintain proper alignment and work together as a team. Each eye has six external muscles (called the extraocular muscles) that control eye position and movement. For normal binocular vision, the position, neurological control and functioning of these muscles for both eyes must be coordinated perfectly.

Early diagnosis is very important in the treatment of strabismus. In most cases, the only effective treatment for a constant eye turn is strabismus surgery. In some cases of intermittent and small-angle strabismus, it may be possible to improve eye alignment non-surgically with vision therapy.