A commonly found glycosphingolipid in the plasma membrane of the cell is galactosylceramide (GalCer), which is known to primarily exist in lipid rafts or domains in the cell membrane. GalCer also plays an important role as an alternative receptor in the sexual transmission of HIV. GalCer allows the HIV protein to enter epithelial cells that would otherwise lack the primary receptor CD4 needed for binding. In this study, different ternary lipid solutions were formed using either 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC), singly unsaturated 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), or doubly unsaturated 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) in combination with GalCer and varying levels of cholesterol. These solutions were then used to make giant unilamellar vesicles (GUVs) in an electro formation chamber. Using 1-palmitoyl-2-[6-[(7-nitro-2-1,3-benzoxadiazol-4-yl) amino]hexanoyl]-snglycero-3-phosphocholine (NBD-PC) as the fluorescent probe, the GUVs were then imaged using fluorescent microscopy. The domain size as a function of the varying levels of cholesterol was determined. This work includes observations of the interactions of the HIV protein, gp120, with GalCer in the phospholipid bilayer.