This paper examines the stresses on coastal plants and plant adaptations imposed in the coastal dune environment. The coastal dune ecosystem experiences severe stresses in the form of salt spray, sand burial, swash inundation, dryness, high light intensity, wind exposure, soil salinity and nutrient deficiency. Common adaptations to these stresses include salt resistance, positive growth response to burial, flooding resistance, leaf roll, photosynthesis, salt bladders, nitrogen fixation, variation of life cycle, germination strategies, and plant morphology to name a few. The level of these stresses is highest in the beach–foredune environment and generally decreases with distance from the coast in fully vegetated coastal dune systems (e.g. relict foredune plains). Plant succession and generally species richness tend to follow these landward-decreasing trends. Blowouts disrupt the most simple systems. Parabolic dunes, when active, display reversed-succession landward trends compared to foredunes and locally disjunct lateral species patterns. Transgressive (mobile) dunefields experience high stress levels (principally a mobile substrate) and locally, slack and deflation basins add cement pavement or standing water stresses. Microenvironments and local habitats are generally lowest on foredunes, moderate on blowouts and parabolics, and highest on transgressive dunefields. On a global scale, warm temperature coasts generally display the highest species richness, lowest stress levels overall, and possibly lowest number of endemic species. As semi-aridity and aridity on coasts increase, there is a trend towards increasing stress levels, lower species richness (particularly in foredunes), less foredune, relict foredune and parabolic dune development, increasing development of transgressive dunefields, less plant cover, more endemic species, and an increasing mixture of desert and coastal species. This paper is dedicated to the memory of Derek Ranwell.