Nitrogen is an essential nutrient for all microbial growth. Yeast cells require nitrogen to grow and complete fermentation. While both organic and inorganic nitrogen are present in grape must, it is common practice in the wine industry to add nitrogen to fermentations. Available products include an inorganic nitrogen source, di- ammonium phosphate (DAP), and an organic nitrogen source, amino acid mixtures. Although both inorganic and organic nitrogen additions to wine fermentations are common practice in the wine industry, it is not well known how the type of nitrogen added impacts the fermentation. This review examines current research to determine what impact, if any, nitrogen source has on alcoholic fermentations in wine and highlights the differences between inorganic and organic sources of nitrogen in alcoholic fermentations in wine.