North-Atlantic and Indian Ocean climate variability appears to be tightly related. The observed increase of the amplitude of the North-Atlantic Oscillation (stronger westerlies) over the past decades is directly related to increased atmospheric convection in response to a warming Indian Ocean. Warm Indian Ocean waters flow into the South Atlantic and further northward as part of the global overturning circulation. Paleoceanographic records indicate that this inter-ocean connection around South Africa fluctuated considerably and abruptly in during (inter)glacial change, as southward transport was the only oceanic pathway for the Indian Ocean to dispose of its excess heat. On millennial time-scales that could explain why warming over the North Atlantic coincided with cooling of the Antarctic sector and vice versa. Observations and modeling suggest an important impact of the Indian-Atlantic inter-ocean connection on the strength and stability of the Atlantic overturning circulation, controlled by the (sub)tropical flows feeding it from upstream. These flows converge in the Mozambique Channel and the southern East Madagascar Current (EMC). North Atlantic and Antarctic cold water masses flow in opposite direction in the deep Indian Ocean. To understand their dynamics, an array of moored instruments will measure interannual variability across the Mozambique Channel and remain in operation for several years. A second array will be placed across the EMC. Combined with satellite data and high-resolution ocean-model simulations a complete picture should emerge of the varying flow in the western Indian Ocean presently feeding into the Indian-Atlantic Ocean connection. Further simulations will be executed under both present and glacial conditions, and assessed against new paleorecords of western Indian Ocean climate change over the past 60,000 years from sediment cores. Finally, simulations with the global climate model EC-EARTH will address the processes controlling the global atmospheric and oceanic (tele)connections between the Indian and Atlantic ocean-climate systems, particularly during abrupt North Atlantic climate change.