Abstract Purpose Obstructive Meibomian gland dysfunction (MGD) is a widespread alteration and represents a main reason for evaporative dry eye syndrome. Hyper‐keratinisation of the ductal epithelium in response to various pathological stimuli appears as a typical underlying reason. Methods Own morphological data together with findings from the literature on Meibomian gland anatomy, physiology and pathology are discussed and used to propose factors and their interactions involved in the pathology of obstructive MGD. Results A large body of literature indicates that obstruction of the Meibomian gland is an important and widespread contributor to the pathology in MGD. Several findings indicate that keratinisation of the ductal system and orifice is the primary factor in obstruction of the gland. Histological and immunohistological data indicate that the whole ductal epithelium of the normal Meibomian gland shows signs of incipient stages of keratinisation, derived from its embryological ancestry. Hence, the gland preserves a commitment to full keratinisation if a proposed developmental block is removed due to various factors. Keratinisation leads to obstructive stasis of secretum inside the gland and to dilatation of the ductal system as well as to atrophy of the secretory acini. This results not only in decreased availability of Meibomian oil on the lid margin and tear film but also to secondary hypo‐secretion. Increase of commensal bacteria and their products may have a certain role in this process although a real infection does not usually occur. Conclusion Events in obstructive MGD which share hyper‐keratinisation as a starting point, interact via different pathways that may form vicious circles and eventually lead to evaporative dry eye and gland atrophy.