Strabismus is a condition where the eyes do not properly align with each other when looking at an object. One eye may turn in, out, up, or down while the other eye focuses straight ahead. This misalignment can occur all the time or only sometimes, and it can affect one or both eyes. People with strabismus may experience double vision or difficulty with depth perception. The condition can develop in childhood or later in life and may be caused by issues with the eye muscles or the nerves controlling them. Treatment options include glasses, eye exercises, or surgery, depending on the severity.