An endoluminal device for implantation in a body lumen reduces movement or migration of the device after implantation by the use of barbs or barb assemblies. A first embodiment uses at least one barb assembly having first and second portions attached to an implant, such as a stent, and at either sides of a bend. The second portion is adapted to protrude radially inward when the implant is in the radially compressed configuration and radially outward when the implant is in its radially expanded configuration. A second embodiment uses a barb having a curved segment which is curved proximally and radially inwardly. A third embodiment utilizes at least one barb assembly having a wire with a length greater than the cell height of the implant across which it extends and a substantially uniform cross-sectional area. Methods for implanting such devices are also contemplated.