Ocular myositis frequently manifests with orbital pain and diplopia. The diagnosis of ocular myositis falls within the overall classification of idiopathic orbital inflammatory diseases, defined as non-infective non-specific orbital inflammation without identifiable local or systemic causes. Orbital myositis may form part of more widespread systemic inflammatory processes such as Crohn's disease and the more recently described IgG4-related disease. There is also a broad range of ophthalmic differential diagnoses. Diagnosis, assessment and management of ocular myositis requires the cooperation of ophthalmologists and rheumatologists/immunologists in order to achieve the best patient outcomes. The current literature and avenues of future research are reviewed.