The molecular mechanism of the store-operated Ca²⁺-entry (SOCE) pathway remains one of the most intriguing and long lasting mysteries of Ca²⁺ signaling. The elusive calcium influx factor (CIF) that is produced upon depletion of Ca²⁺ stores has attracted growing attention, triggered by new discoveries that filled the gap in the chain of reactions leading to activation of store-operated channels and Ca²⁺ entry. Ca²⁺-independent phospholipase A₂ emerged as a target of CIF, and a major determinant of the SOCE mechanism. Here, we present our viewpoint on CIF and conformational-coupling models of SOCE from a historical perspective, trying to resolve some of the problem areas, and summarizing our present knowledge on how depletion of intracellular Ca²⁺ stores signals to plasma membrane channels to open and provide Ca²⁺ influx that is required for many important physiological functions.