According to Billboard chart statistics, Chicago is second only to the Beach Boys as the most successful American rock band of all time, in terms of both albums and singles. If that fact's surprising, it's because Chicago has been singularly underrated since the beginning of their long career, both because of their musical ambitions and because of their refusal to emphasize celebrity over the music. By those standards, Chicago has succeeded in the ways they intended to. From the beginning of their emergence as a national act, they've been able to fill arenas with satisfied fans. And beyond the impressive sales and chart statistics, their music has endured, played constantly on the radio and instantly familiar to tens of millions.