In this tribute to Bill Whelan on his 90th birthday, I recount the huge impact that Bill has had on my life and career, and briefly recall the contributions that my laboratory made to the understanding of glycogenin in the late 1980s. In particular, the demonstration that glycogenin and glycogen synthase form a complex, and that glycogenin is a glucosyl transferase that autoglucosylates itself at tyrosine 194.