This chapter discusses the procedures employed for the analysis of the sugar components of glycoproteins. Most of the methods used for the estimation of the monosaccharides present in glycoproteins are colorimetric in nature. Because of the relatively low specificity of some of these color reactions, it is often important to apply them only after appropriate separation of the constituents. In many cases complete identification, preferably by chromatographic means, of all the sugar and amino acid constituents of a glycoprotein should precede any colorimetric analysis so that potentially interfering substances may be taken into account. The hydrolytic release of the monosaccharides is also considered in the chapter. The optimal conditions of acid hydrolysis for the monosaccharides vary substantially because of differences both in the stability of their glycosidic bonds and in their susceptibility to destruction during the hydrolysis. One of the prerequisites for an accurate analysis of the monosaccharide components of a polymer is finding hydrolysis conditions under which all of a given sugar is released and yet is not significantly destroyed.