Increased calcium absorption from the gut is the primary function of vitamin D in the regulation of calcium levels in the body. This article provides a description of the early research that laid the groundwork for the first model of vitamin D-mediated calcium absorption. In addition, a review is made of other research that pertains to the function of vitamin D in the intestine, including studies that have cast doubt on the validity of the conventional model and shed light on the crucial part played by certain calcium transport proteins. The more recent work that has been done to identify novel targets of 1,25(OH)2D3 action in the intestine is summarised, together with the work that has been done to highlight the importance of 1,25(OH)2D3 action across the proximal/distal and crypt/villus axes in the intestine.