Acne is a chronic inflammatory disease of the pilosebaceous unit resulting from androgen-induced increased sebum production; altered keratinisation; bacterial colonisation of hair follicles on the face, neck, chest and back by Propionibacterium acnes; and an inflammatory response in the skin. The exact way these processes interact and the order in which they occur in the pathogenesis of acne are still unclear. Scarring that occurs from acne, particularly severe acne, can persist a lifetime and have long lasting psychosocial effects. Depression, social isolation and suicidal ideation are frequent comorbidities in acne. Despite the plethora of topical and systemic treatments available for acne, there is a relative lack of quality evidence for its application. Of the systemic treatments available, oral isotretinoin remains the most effective well established treatment for acne that targets all the aetiological factors. Current guidelines for the treatment of acne are based largely on expert consensus and advocate a combination of topical agents in mild to moderate cases and reserve the use of systemic therapies for moderate to severe or refractory cases of acne. However, given the psychosocial impacts of acne, there is a strong argument for early, effective treatment with systemic therapy when topical and general measures have failed.