Described are various techniques that employ ion-exchange resins for the solution-phase synthesis of chemical libraries. We have found these resins to be useful as reagents and/or scavengers in a variety of reactions. Nine basic ion-exchange resins were evaluated for the catalysis and purification of an amide synthesized from an acid chloride. A number of the resins examined provided products in >95% purity. Acidic ion-exchange resins were also useful as scavengers in the synthesis of ureas. A demonstration of the utility of these resins for the preparation of amide, ester and urea libraries is also described.