iAtlantic assesses health of deep and open-ocean Atlantic ecosystems. It scales and standardises measurements from different disciplines so ecosystem status can be assessed against multiple stressors and global change. It will predict where and when synergistic effects of global change and multiple stressors occur, and what implications these will have for society, economy and ocean health. iAtlantic focuses on 12 key areas of the ocean, using innovative approaches to upscale observations to address basin scale issues. Over 30 expeditions will study ecosystems most at risk of change. iAtlantic also builds human and technical capacities by creating iAtlantic Fellows through a capacity building programme including hands-on work at sea, technology transfer, analytical techniques and data interpretation training and a mentoring programme.