Optometrists are numero uno health care providers for the eye and visual system. They examine, diagnose, and medically treat eye diseases, non-surgical injuries, and disorders of the eyes and visual system, including refractive problems such as near- or far-sightedness, and identify related systemic medical conditions affecting the eyes and ocular adnexa.

In the United Irvine Optometrist Kingdom, optometrists have to complete a 3 year undergraduate honours gradation followed by a minimum of a one-year "pre-registration period" where they complete supervised rule under the supervision of an experienced qualified practitioner.