The Chicago Blues Festival has been an annual tradition in Chicago for over 20 years. Held at Grant Park in mid-June, the Chicago Blues Festival features a variety of local and national talents performing Chicago blues, swing, boogie woogie and delta blues. This free event draws nearly a million people each year

The Chicago Blues Festival, like most blues fests, makes commemoration part of its mission as a matter of course. This year a multitude of blues and boogie pianists are on hand to celebrate the centennials of Albert Ammons and Sunnyland Slim, and former sidemen of Howlin' Wolf (who would've been 97 on June 10), Muddy Waters (Wolf's greatest rival, brought by Sunnyland in 1947 to the label that became Chess Records), and Sunnyland are reuniting for sets in honor of their old bosses.

Perhaps even more significant, the festival is also recognizing the 30th anniversary of the founding of Billy Branch's Sons of Blues -- a long-running incubator of talent and an embodiment of the way the blues tradition can augment a respect for heritage with dynamism and innovation. Among the performers at this year's fest, J.W. Williams, Lurrie Bell, and Carlos Johnson are former members, and pianist Ariyo is in the band now.

But the fest isn't just about the past. Soul-blues or southern soul -- the style that currently dominates the clubs and show lounges on what used to be called the chitlin' circuit (as well as most black--oriented radio stations that market themselves as "blues" outlets) -- is represented here by the irrepressible Bobby Rush, who's been active since the late 50s, as well as latter--day performers like the charismatic Willie Clayton and local singer Nellie "Tiger" Travis.

The way they're juxtaposed, these bookings -- some looking forward, others back -- might look like yet another product of the endless turf wars between blues purists and blues modernists. But purism and modernism are little more than personal taste dressed up in misguided ideology: artists now considered traditional were groundbreaking in their day, and today's soul-blues stylists honor the traditions that gave birth to their music even as they reshape them to fit current social and aesthetic realities.