It may be that in musical retrospect, from a luxury of twenty-twenty critical hindsight, that Astor Piazzolla will be seen as having done in the twentieth century for the tango what Frederick Chopin did in the nineteenth for the waltz. It is perhaps already an accepted position. With the waltz, Chopin took an established popular form and stretched its boundaries so that what an audience might have expected to be a little ditty was recast to express heroism, sensuality, pride or even occasional doubt. The little dance tune then, in Chopin