CAPROSYN* suture is the latest innovation in monofilament synthetic suture. This suture is prepared from POLYGLYTONE*6211, a synthetic polyester composed of glycolide, caprolactone, trimethylene carbonate, and lactide. The purpose of this study was to compare the biomechanical performance of CAPROSYN* suture to that of CHROMIC GUT suture. The biomechanical performance studies included quantitative measurements of wound security, strength loss, mass loss, potentiation of infection, tissue drag, knot security, knot rundown, as well as suture stiffness. Both CAPROSYN* and CHROMIC GUT sutures provided comparable resistance to wound disruption. Prior to implantation, suture loops of CAPROSYN* had a significantly greater mean breaking strength than suture loops of CHROMIC GUT. Three weeks after implantation of these absorbable suture loops, the sutures had no appreciable strength. The rate of loss of suture mass of these two sutures was similar. As expected, CHROMIC GUT sutures potentiated significantly more infection than did the CAPROSYN* sutures. The handling properties of the CAPROSYN* sutures were far superior to those of the CHROMIC GUT sutures. The smooth surface of the CAPROSYN* sutures encountered lower drag forces than did the CHROMIC GUT sutures. Furthermore, it was much easier to reposition the CAPROSYN* knotted sutures than the knotted CHROMIC GUT sutures. In the case of CHROMIC GUT sutures, it was not possible to reposition a two-throw granny knot. These biomechanical performance studies demonstrated the superior performance of synthetic CAPROSYN* sutures compared to CHROMIC GUT sutures and provide compelling evidence of why CAPROSYN* sutures are an excellent alternative to CHROMIC GUT sutures.