The properties of cobalt-chromium alloys which have recently been introduced in several new generations of vascular stents will be reviewed. Physical and mechanical properties of L605, MP35N and Phynox/Elgiloy are compared and discussed in relation to stent performance. With a higher elastic modulus and density, L605 stands out as a preferred stent material and its behavior is further investigated. Tensile data and microstructural observations are presented for tubing annealed under various conditions of time and temperature. It is shown that although material properties can be adjusted over a wide range, optimization of stent performance can be achieved with tight control of tube processing parameters.