The physical properties of polyglactin 910 (Vicryl) have been studied experimentally and clinically and compared with other synthetic and natural suture materials. Polyglactin 910 has a relatively high fluid absorption capacity but a low capillary capacity. The tensile strength is high and well comparable with, or superior, to other synthetic non-absorbable suture materials commonly used. The elongation at break is moderate. No unfavourable wound reaction to the suture material has been registered. The material has not increased the expected frequency of wound infections. The follow up of laparotomized patients 12-18 months after the operation showed a very low frequency of wound hernia. Neither was any recurrence noticed after repair of inguinal hernia. No clinical signs of leakage in the anastomoses of the gastrointestinal region was registrated. It is concluded that polyglactin 910 in a wide extent seems to be able to replace catgut and also non-absorbable suture materials when normal wound healing is to be expected.