They are fronted by vocalist/keyboardist/guitarist Bill Champlin, who was also a member of the rock band [a=Chicago (2)].

Years active
1965–1970
1971–1977
1985
1997–Present

Members
Carmen Grillo (2005–)
Geoffrey Palmer (1967–)
David Schallock (1971–)
Bill Champlin (1965–)

Past members
James Preston (1971-2015)
Tim Cain (1965–1970)
Terry Haggerty (1965–1977, 1997–2001)
John Prosser (1965–1967)
Jim Meyers (1965–1967)
Jim Beem (1967–1970)
Al Strong (1967–1970)
Bill Bowen (1967–1970)
Bill Vitt (1971–1972)
Mark Isham (1972-1974)
Tal Morris (2001–2005)
Mic Gillette (1998–2006)