Introduction
Dry eye disease (DED) is among the most common chronic ophthalmic conditions encountered in clinical practice. The Tear Film and Ocular Surface Society’s Dry Eye Workshop II (TFOS DEWS II) was convened to review the contemporary literature with the aim of providing an evidence-based global consensus view of the current understanding of DED. 

Discussion 
An updated definition and classification scheme was introduced, highlighting tear film homeostatic disturbance as a central hallmark of DED, and acknowledging the substantial overlap between the two aetiological subtypes, aqueous tear deficiency and evaporative disease, which are viewed to exist as a continuum. 

Streamlined diagnostic criteria for DED were developed for the first time, and require the presence of both clinical signs and symptoms of tear film homeostatic disruption. A global consensus management algorithm was proposed, and provides a framework for treatment initiation with conventional, low-risk, easily accessible patient-applied therapies in early-stage disease, followed by progression to more advanced management therapies targeted at particular pathophysiological aspects of DED. In addition, the underlying aetiological causes and pathophysiological mechanisms of DED were outlined, and a systematic literature review was conducted on the population prevalence patterns, natural history and risk factors for the condition, including age, sex, comorbidities and iatrogenic causes.