The bursting strength of sutured and laser-welded vascular anastomoses were assessed in a rat aorta model. Postoperative investigations included postmortems, light and scanning electron microscopy and measurements of bursting strength at set intervals (30 min, 3, 14 and 28 days postoperatively, p.o.). Laser-bonded anastomoses consistently demonstrated lower bursting strengths than suture controls, with statistically significant differences at 30 min and 3 days p.o. (p < 0.01). Laser anastomosis was easier and faster to perform, the foreign body reaction was markedly lower than in sutured controls. Formation of aneurysms was not observed.