Dairy cows respond to the challenges of the transition period in ways that are both dynamic and cow specific. This is especially true for the challenge of maintaining calcium balance immediately following calving. With the onset of lactation, cows begin secreting copious amounts of calcium in their milk, to the extent that their dietary intake cannot compensate for the loss of this essential mineral. Cows must coordinate a response to this challenge to maintain calcium balance, and those that fail to do so often develop milk fever, or clinical hypocalcemia. While this is certainly an important disease, prepartum diet management, and well-established treatment protocols minimize the impact that milk fever has on cows and herds. For cows that do not develop milk fever, individual dynamic responses to the early lactation calcium challenge are varied. These individual responses can be identified by measuring blood calcium at one and four days in milk (DIM), such that the dynamics of calcium at and between these timepoints can classify individual cows into one of four “calcium dynamic groups.” Each group is associated with different health and production outcomes that, for the sake of this article, we consider: worst, at risk for negative health outcomes and producing the least milk; bad, at risk for negative health outcomes but producing decent to appreciable amounts of milk; good, consistently healthy and producing average amounts of milk; and excellent, consistently healthy and producing exceptional amounts of milk.