Preferred embodiments of a stent with a high degree of flexibility are shown and described. The stent can include a continuous helical winding having interconnected struts joined at vertices, and having bridges connecting sections of the helical winding to each other. An annular ring can be provided at one or both ends of the helical winding, and the annular ring can have extensions extending to connect to the helical winding. One of the extensions can connect to a bridge and another extension can connect to a vertex. The struts at the ends of the helical winding can have strut lengths that differ from the strut lengths of the struts in a central portion of the winding between the ends of the winding.