I signed him from St Mirren for Leicester City and he is a terrific man who took over Derby at a low ebb.
He has changed so many players - only a few have survived the cull - and the club has flourished.
But I'm also delighted for Derby, who finished eight points clear of West Brom in the table.
Although these play-offs are an exciting, money-making idea, they are nerve-wracking and you like to see the team finishing third finally emerge because they've done it over the course of the season.
And I'm delighted because Derby is a town of great football tradition with great players like the Hectors, McFarlands, Todds, Dave Mackay... and now all the supporters will be talking about recreating those times.
There was unbelievable tension at the end as they inched closer to the Premiership, but they survived.
They survived the first half when West Brom were the smoother side, the dominant side, and they survived Albion's frenetic attacks at the end.
By then Tony Mowbray had made changes designed to make his side more attack conscious, but I felt one or two changes didn't benefit them, with Jason Koumas coming inside and Diomansy Kamara going out wide.
But Derby kept at it the whole match, their game plan worked and they allowed West Brom few chances.
Barnes was an inspired substitution and was almost immediately involved as Derby scored that crucial goal.
He made a terrific run behind Paul Robinson to play in Stephen Pearson and from that moment on Derby grew in stature, grew in heart and became a team.
Some of their players were excellent, particularly in defence where Dean Leacock was superb and Moore was a tower of strength the whole game through.
They had stickability, a lot of determination, drive and team spirit.
However they will need to make changes over the summer, as will Sunderland and Birmingham.
Every team that goes up knows there is a gulf to bridge, but Billy has good contacts, has his ear to the ground, is not frightened to pick up the phone and ask advice and he will find players to better his side.
Although he needs to be wary and he needs to look at what Steve Coppell's done with Reading.
He needs to keep the spirit, coach well and add frugally and be as single-minded, honest and straightforward as he has been so far.
Just like Sunderland and Birmingham, Billy and Derby need to aim to survive the first year in the Premiership, and those first few months can help give them self belief.
It will be difficult for all of them.
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Billy Davies is a football fanatic, a little man with a big heart and I'm delighted for him Derby went up.
