Increased functionality and power consumption of microdevices and high power electronics has come at a cost: power dissipation and heating. This heat must be dissipated to ensure reliable operation of such devices in both earthly and reduced gravity environments (eg space industry), without adversely affecting their performance. With a highly competitive world market, worth tens of billions of Euros, it is imperative for EU to gain a competitive position in this field (currently led by USA and China).The proposed work is an important step towards developing novel, efficient and reliable thermal management via phase-change through international collaboration between top research groups in EU, USA and China. These include 12 experienced researchers from University of Edinburgh, Shanghai Jiaotong University, Ecole Polytechnique Fédérale de Lausanne, University of Maryland and University of Nottingham. These partners have complementary expertise in microfabrication, experimental techniques, analytical and numerical modelling. The collaboration enables knowledge transfer and access to unique facilities such as those at NASA, Intel, Hua Wei and IBM, reinforcing the research standing of EU in this crucial technological area. It also offers an opportunity for training 20 early stage researchers in state-of-art experimental and modelling techniques.The collaboration exploits and extends ongoing studies in two-phase flow and heat transfer by the partners. These comprise studies in pool boiling, evaporation, flow boiling and condensation, adapting and optimising these for thermal management of micro/optoelectronics systems. The objective is towards developing an integrated cooling system within electronic microdevices interfaced with an external circuit to take advantage of strengths in high energy efficiencies of phase-change. Potential applications cover devices such as cellphones, refrigeration systems, supercomputing clusters and space equipment.