The leading cause of Diplopia or Double Vision is Convergence Insufficiency. Diplopia occurs when the eyes are not aimed at the same target. The slight eye turn found in Diplopia the patient in many instances will report seeing everything twice, “Double Vision”. Convergence Insufficiency is an eye muscle condition in which the eyes do not cross or converge when looking upon an object at close range, thus causing difficulty seeing things close up. Convergence Insufficiency is the leading cause of eyestrain, blurry vision, Diplopia (Double Vision), and/or headaches. Consult with a doctor for more information regarding Diplopia and/or Convergence Insufficiency as well as diagnosis and treatment options.