Brian Clough of course famously managed both clubs, while his son Nigel wrote his name into the history books at Forest before going on to manage the Rams.
Clough isn’t the only man to have occupied the hotseat at both clubs with Billy Davies and Steve McLaren also joining that small club.
Like Clough jnr, Colin Addison played for Forest before managing Derby, while Mick Harford did it in the opposite order.
There’s also been plenty of players who have played for both clubs down the years – perhaps more than you think.
So with that in mind, here are just some who have crossed the big East Midlands divide.
9. Steve Sutton
During his time with Forest Sutton made 257 appearances across all competitions, and won the League Cup and Full Members' Cup twice each. He had a brief loan spell at Derby, while a Forest player, in 1985 before a longer spell with County between 1992 and 1996. Photo: Getty Images
10. Colin Todd
Colin Todd joined Derby in February 1971 for a British record transfer fee for a defender of £175,000. Todd helped Derby win the First Division title in his first full season at the Baseball Ground and collected a second title winner's medal under Clough's successor Dave Mackay in 1975. He had a less successful spell for Forest, playing 36 times between 1982 and 1984. Photo: Getty Images
11. Daniel Ayala
Daniel Ayala will easily be forgotten by both sets of fans. He played 17 times on loan for Derby in 2001 and 12 times for Forest while on loan from Liverpool in the 2012/13 season. Photo: Getty Images
12. Patrick Bamford
Bamford began his career at Nottingham Forest, making his debut in December 2011, at the age of 18. A month later he joined Chelsea for a fee of £1.5 million. It didn't pay off with a series of loan moves following, including 21 games in 2014 with Derby, where he scored 8 goals. Photo: Getty Images