Assessment of the properties of lignocellulosic materials prior to and after pretreatment and enzymatic modification is important in determining the commercial potential and feasibility of the processes. The effect of treatments on the degree of polymerization (D.P.) of cellulose and carbohydrate composition are particularly important in the evaluation of treatments of commercial pulps with enzymes. Improved understanding of the effect of pretreatment conditions and subsequent treatments on D.P. of cellulose in the substrates will aid in development of a more efficient enzymatic hydrolysis process. The determination of the D.P. of cellulose in pretreated forestry residues will also aid in the identification of alternative polymeric products. A method was developed for determining the molecular weight distribution of lignocellulosic materials. The method of choice was derivatization of the substrate to the carbanilate followed by size exclusion chromatography. A number of possible variables in the method were investigated and a microscale procedure developed. This procedure was used to provide molecular weight distribution data for both softwood and hardwood pulps subjected to xylanase treatments. The method was also used to study the effects on the cellulose in aspenwood and sprucewood of differing steam pretreatment conditions, and post treatments (hydrogen peroxide). These studies highlighted the limitations of the method when analyzing lignocellulosic materials with significantly higher lignin contents than the pulps for which it was originally intended. More importantly, the studies indicated that depending on the treatment conditions used, celluloses of substantially different average D.P. and polydispersity can be produced. Analysis of carbohydrate in lignocellulosic materials continues to be critical to any study involving residue utilization by bioconversion. Development of methods for HPLC analyses of carbohydrates were monitored with emphasis on the use of electrochemical detection methods. The state-of-development of these detectors is discussed.