HTS cables promise a number of special benefits in terms of their high current carrying capacity, reduced electrical losses, compact overall dimensions, low weight and minimal environmental impact. This paper describes four application-focused HTS cable projects in progress within the Pirelli Group, to demonstrate the feasibility of `warm dielectric' and `cold dielectric' HTS technology at medium and extra high voltage. Particular attention will be devoted to the Pirelli-EPRI-DoE project that was successfully concluded in January 1999 with the demonstration of a 50 m 400 MVA 115 kV pipe-type retrofit HTS cable system capable of carrying 2 kA_rms ac. Details on the final high voltage tests and ac loss measurements are reported.