The 4th Symposium on The Extracellular Calcium-Sensing Receptor (CaSR) and three of its highly successful precedential meetings are the only conferences that bring together a very diverse mix of international scientists and clinician-scientists interested in the molecular and cellular mechanisms that govern physiological and pathological actions of the receptor in different organ systems. There is a strong focus on novel actions of the receptor in calciotropic tissues (i.e., parathyroid gland, kidney, and bone) controlling mineral and skeletal homeostasis and in those mediating neuronal, pulmonary, cardiovascular, skin, intestinal, immune, and metabolic functions and their associated diseases, including multiple forms of cancers. Translational studies of preclinical animal models and clinical research to assess pharmaceutical potentials for disease prevention and treatment by targeting the CaSR are also the meeting highlights. The Specific Aims of the 4th International Symposium on CaSR are to deliver a program that addresses key scientific questions and controversies for the field, generates integral views on CaSR actions in diverse organ systems, evaluates off-target effects of the current calcimimetics/calcilytics therapies, and assesses potentials of devising CaSR-targeting therapies for treatments of disorders beyond the mineral diseases. The latter disorders include energy and metabolic dysregulation, vascular calcification, pulmonary hypertension, asthma, osteoporosis, osteoarthritis, bone fracture, skin wounding, inflammatory blood and bowl diseases, neurodegeneration in stroke and Alzheimer’s disease, neuroblastoma, and colon and breast cancers. International experts are invited to address the following topics: (1) CaSR structure and gene regulation; (2) receptor signaling and trafficking; (3) CaSR actions in renal pathophysiology; (4) CaSR actions in lung/blood/vessel diseases; (5) the roles of CaSR in gastrointestinal and inflammatory functions; (6) CaSR actions in CNS functions; (7) CaSR actions in glucose and energy homeostasis; (8) CaSR actions in skeletal and ectopic calcifications; (9) CaSR actions in cancer development and treatment; (10) signaling cross-talk of CaSR with other cellular functions; (11) novel CaSR actions in mediating parathyroid functions and diseases (studies of preclinical mouse models); (12) current states of clinical treatments of parathyroid diseases by targeting CaSR; and (13) potentials of repurposing CaSR modulators for novel disease treatments. A “passing-the-torch” theme guides the design of the scientific program to include early-stage investigators (ESIs) in session co-chairships, podium presentations, opportunities to meet with established investigators, and travel awards. A final group discussion will be conducted to generate a consensus to guide future collaborative research, clinical uses of CaSR modulators, and development of novel therapies.