This invention relates to an unidirectional barbed suture for connecting human or animal tissue, said suture comprising an elongated body having a longitudinal axis, a cross-sectional distance or diameter (SD), a first end and a second end, where a needle having a needle diameter (ND) is attached to the first end and a needle is not attached to the second end and a plurality of barbs projecting from the body towards the second end wherein the barbs are staggered along the body in three sets with 120 degree spacing between any two sets and a plurality of barbs comprising a configuration wherein a ratio of a barb cut depth (D) to the cross-sectional distance or diameter (SD) is about 0.05 to about 0.6.
