This publication reviews work done in the authors＇ laboratories on the functionalization of surface-reactive polymers and their application as a basis for the preparation of oligonucleotides of extended length, larger number or quantity. In addition to nonporous particulate materials (silicagel microbeads; polystyrene-grafted polytetrafluoroethylene particles) special focus is on recent work describing the introduction of spacered amino groups into polypropylene films and the preparation of oligonucleotides on polypropylene surface. A prototype apparatus is shown, for use with a four-column DNA synthesizer, that permits the semi-mechanized preparation of a one-dimensional array of oligonucleotides of variant sequence.