It is now well documented that Arctic climates and ecosystems are changing at some of the fastest rates on planet Earth. These changes are significant for all Arctic biodiversity, and they are a great challenge for cooperative management boards of Canada's Arctic national parks, those legislated to maintain or improve the ecological integrity of all national parks. Owing to the inherent complexity of natural ecosystems, it is not at all clear how, nor how rapidly, these ongoing changes will affect park biodiversity and impact the traditional land-based lifestyles of Indigenous park cooperative management partners. In this context, this paper reviews and integrates recent research carried out in Canadian Arctic national parks: (1) geophysical - a reduction in glacial area and volume, active layer thickening, warming soil temperatures, and terrain instability; (2) vegetation - widespread but ecosystem-specific increases in NDVI 'greenness', plant biomass, shrub and herb coverage, and growing season lengths; and (3) wildlife-complex changes in small mammals and ungulate populations, very negative effects on some polar bear populations, and relatively stable mammalian predator and raptor populations at this time. This work provides a partial snapshot of ongoing and evolving ecological effects of climate change in Arctic national parks, and provides a strong foundation for prioritising future research and monitoring efforts. These evolving changes also undermine the historical paradigm of place-based conservation and necessitate a new approach for managing protected areas that involves acceptance of ongoing transformational change and adoption of a risk-based, forward looking paradigm in a changing world. It is proposed that Arctic national parks are ideal locations to focus Arctic science, especially as a component of a strategic, coordinated, and pan-Arctic approach to Arctic research that makes the most effective use of limited resources in the vast areas of Canadaâ¿¿s north.