Protein phosphorylation has been recognized as one of the most versatile mechanisms that underpin several critical adaptive and developmental processes in plants serving as fast and accurate process to message signals within the cells to generate nuclear responses. Advances in functional dissection of canonical signalling pathways demonstrate that protein phosphatases and their substrate kinases are key determinants in developmental decisions and plant stress tolerance. Plant protein phosphatases of PP2C-type are essential components opening new approaches for deciphering the very early events in cell signalling. This project, aided by the combinations of multidisciplinary cutting-edge technologies, such as proteomics, phosphoproteomics, bioinformatics, molecular biology and metabolomics, is expected to precisely identify the protein associations assembled upon stress conditions and developmental processes through PP2Cs in the model plant Arabidopsis. Research and training in highly developed technologies are expected to stimulate European competitiveness in resolution of cell signalling mechanisms by proteomic tools, uncover the links to metabolic pathways and reinforce further innovations with significant scientific impacts. “ProMet” is introducing EU priority research directions and topics, providing the advanced excellence in molecular biology, proteomics and metabolomics to carry out interdisciplinary technical developments important not only for plants but for life sciences in general. Uncovering the functions and targets of signalling components phosphatases that control key developmental and stress signalling pathways is an essential task that finally affects the environmental issues, future innovations and socio-economic impacts.