The Celtic v Rangers clash in Glasgow is one of football's major events, attracting a huge TV audience worldwide.
Author David Potter revels in the joy that a victory over the old rivals brings to the Celtic support, reliving some of the club's greatest ever derby-day triumphs from the 1890s right up to date.
Here is an expert selection of 50 such legendary occasions, rich in detail and atmosphere, and all the topic of fervent discussion over the years.
We hear of Jimmy Quinn's hat-trick in 1904, the astonishing Scottish Cup semi-final of 1925, the 7-1 Scottish League Cup Final of 1957, the 4-0 thrashing in the 1969 Scottish Cup Final, the 6-2 'Demolition Derby' of 2000, plus many landmark games of a more recent vintage.
Celtic's greatest players - Henrik Larsson, Jimmy McGrory, Patsy Gallacher, Charlie Tully, Jimmy Johnstone, Billy McNeill and Scott Brown - appear frequently in these pages, as do many others who all played their part in what is traditionally the greatest party of them all, when Celtic beat Rangers!