Predicted global warming as a consequence of rising atmospheric concentrations of greenhouse gases is anticipated to force reorganization of alpinoboreal ecosystems. On these premises, the objective of this paper is to make tentative projections of subalpine/alpine plant cover performance over the present century in the Scandes Mountains of Sweden. This effort draws on paleovegetation data; reversal of a consistent Holocene cooling trend, and monitoring of the concerned system over the past century with predominant climate warming. On all time-scales, upper elevational species limits respond idiosyncratically and without appreciable time-lag to climate warming. Ecological impacts are largely mediated by snowmelt timing. Treelines and upper limits of subalpine/alpine vascular plants are projected to rise by at least 500 m, given a mid-range projection of 3 °C secular warming. Over large parts of the landscape, however, strong or even strengthened wind exposure retards, reduces or prohibits this expansion and particularly the establishment of trees and closed forest. Thus, the alpine character of the landscape largely remains, while the ground cover takes on a denser and more luxuriant appearance. Upward plant migration implies a significant rise of species richness at high elevations, which possibly enhances ecosystem stability. Nothing suggests that rare and strongly specialized alpine plant species will be regionally extirpated or totally extinct in this region. Geomorphic instability (wind, water) in treeless alpine areas counteracts closure of the ground cover. Reproduction and vigour may even become stimulated for this group of species. Species-specific plant responses tend to upset traditional biogeographic zonation schemes, based on diagnostic species. Plant communities dependent on late snow-lie, i.e. alpine snowbed vegetation, alpine mires, subalpine birch forest and montane spruce forest lose substantially in prominence. With future climate warming, Pinus sylvestris resumes the dominant role in forest-alpine tundra ecotone it had during the thermal optimum in the early Holocene.