Convergence is a symmetrical motion converging both eyeballs.

A deficiency of convergence occurs not only in cases of exophoria and divergent strabismus, but also sometimes in convergent strabismus, especially alternating strabismus. Convergence exercises are carried out before and after the surgical procedure. Before surgery, exercises are used to enhance convergence (which may also be weak in convergent strabismus) to prevent secondary deficiency after surgery. Sometimes convergence exercises are used as a supplement to orthoptic exercises, in cases which do not require surgery, eg in convergence deficiency, severe exophoria, intermittent divergent strabismus.