Inflammatory breast cancer (IBC) is the most aggressive and lethal manifestation of local advanced breast cancer with the inherent ability to rapidly metastasize/spread throughout the body. IBC carries an extremely poor prognosis, and the low survival rate of IBC is due to the highly invasive nature of the disease. Specifically, IBC has a proclivity to invade and block the dermal lymphatics of the skin overlying the breast, allowing the disease to spread rapidly, and making it the most lethal form of breast cancer. Because of the aggressive, invasive, and lethal nature of IBC, therapeutics are desperately needed. Vitamin D is a known regulator of cancer cell apoptosis, proliferation, migration, and invasion. Recent studies in various cancer types have suggested vitamin D may be able to inhibit the ability of cancer cells to move. The goal of this study was to determine the impact of Vitamin D on inflammatory breast cancer cell phenotype, proliferation, apoptosis, and migration capabilities. The results from this study suggest that Vitamin D modifies cellular phenotype, and decreases proliferation and migration of IBC cells, with no significant impact on cell death.