This study assembles current and new information on the mechanisms involved in intracellular calcium regulation and their actual or potential relationship to cellular calcium transport. Topics discussed in detail are calcium channels, cellular calcium extrusion, sodium/calcium exchange, calcium-binding proteins with special reference to the vitamin D-induced calbindin, calcium transport and disorders thereof. Each topic is introduced with an overview followed by research papers dealing with relevant topics in each category. New information deals with calcium channels which are not voltage-sensitive, the structure and function of the plasma membrane Ca ATPase, the role of the Na/Ca exchanger in intracellular Na and proton regulation, a comprehensive overview of calcium transport with quantitative analysis of the role of the intestinal and renal calcium-binding proteins, description of the structure and function of the calbindin genes, and identification of calcium transport defects in diabetes and hypertension. Readers will be brought up-to-date on current knowledge and concepts in this rapidly expanding field and be directed to the relevant primary and secondary literature.