The Irish international joined us in March 2000 and, playing both up front and in defence, it was almost a year before he make his mark with vital goals in our run to the FA Cup semi-finals in 2000-01.
But just as he looked like cementing a position in central defence he suffered a broken leg in a League Cup tie against Torquay in September 2001 that kept him out until April 2002.
Since then he's settled into a defensive role - although still playing up front for Ireland (four goals in 22 caps) - and he's now made 69 appearances in all competitions.
Acting boss David Pleat said: "Gary came from Luton three years ago, he did well up front, helped us win a couple of important FA Cup ties but then he broke his leg and went backwards.
"We never adjusted his contract, the whole thing was put on ice and he was the victim of circumstances so we're pleased to give him the opportunity to sign a new contract.
"I think he's done ever so well since he's played centre-back. He had a terrible time against Leicester City but that was a good opportunity to say 'we believe in you and you have a future here'.
"Indeed, Doherty and Gardner looked a very good combination in that little run of games when we beat Leeds and Liverpool. I thought that looked an interesting combination.
"Then, like all players, he had a little slip back, made those errors against Leicester and that probably shook him.
"But I'm pleased with him. He's a very genuine player and I think he can only improve."
Gary Doherty has signed a new deal to extend his career at White Hart Lane.