All living cells in a multicellular organism critically depend on efficient ways of intercellular communication. One of the most extensively used transmembrane signalling module in nature is the G protein-mediated signalling system [1,2]. G protein-coupled receptors, G proteins, and effectors are expressed in all mammalian cells and upon activation evoke a host of cellular responses. Calcium is an ideal second messenger in cells, because due to the enormous concentration gradient of over 4 orders of magnitude many external stimuli can rapidly elevate the intracellular calcium concentration ([Ca 2+ ] i ) and set in motion a variety of cellular processes like contraction, secretion, and gene transcription. Activation of phospholipase C (PLC)-β isoforms by G protein-coupled receptors or of PLC-γ by receptor tyrosine kinases results in the hydrolysis of phosphatidylinositol-4,5-bisphosphate (PIP 2 ) and the resultant formation of the second messengers diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP 3 ) [3]. The ensuing rise of [Ca 2+ ] i is brought about by entry of external Ca 2+ via nonselective cation channels in the plasma membrane, a process referred to as receptor-operated Ca 2+ entry (ROCE) and IP 3 -induced release of Ca 2+ from internal stores. The depletion of intracellular Ca 2+ stores is the trigger for Ca 2+ entry through highly Ca 2+ selective plasma membrane ion channels. The latter phenomenon is called store-operated Ca 2+ entry (SOCE) [4,5].In the recent past, novel biophysical, genetic, and pharmacological approaches have granted deeper insight into single components of such complex signalling cascades. However, the functional interplay of defined signalling modules still remains ill understood. As a springboard to disentangle the intricacies of cellular Ca 2+ signalling sparked by receptors and G proteins, an international symposium was organized at the Max Delbrück Center in Berlin, Germany, November 21-22, 2014, supported by the German Center for Cardiovascular Research (DZHK), Max Delbrück Center, Berlin-Buch, and Transregional Collaborative Research Center 152 (TRR 152). The scientific aim of this symposium was to bring together the receptor/cyclic nucleotide and calcium signalling communities in order to better understand the integration of cellular signalling with a special focus on the cardiovascular system (Fig. 1). Receptors, G proteins, and Ca 2+ permeable ion channels are central signalling modules orchestrating cardiovascular functions. The symposium had the focus on the integration of receptor, G protein-, and calcium-mediated cellular signals underlying complex cellular functions. Because of his role as a catalyst of our advance in knowledge in this research area, the organizers also sought to feature the lifetime achievements of Lutz Birnbaumer as a major international player in G protein and Ca 2+ signalling research for over five decades. A synoptic approach was chosen to attain a deeper mechanistic understanding of physiological regulation and pathologic dysregulation...