John Illsley (born 24 June 1949 in Leicester, England) is a British musician. In 1977 the bassist Illsley founded the British band Dire Straits together with Mark Knopfler (guitar), his brother David Knopfler (guitar), and Pick Withers on the percussion drummer, playing alongside Mark Knopfler as the only founding member until the dissolution in the 1990s ,In the 1980s, he released two solo albums, Never Told a Soul (1984) and Glass (1988), where Mark Knopfler helped him with the guitar.  In June 2002, Mark Knopfler hosted four charity concerts in London, where Illsley and other ex-Dire Straits members (Guy Fletcher on the keyboards, Chris White on the saxophone and Danny Cummings on drums) stood. After suffering from chronic leukemia for many years Illsley had to undergo a stem cell transplant and is considered to be cured today.  In 2015 he went on a European tour with his live band, which included the guitarist Phil Palmer.