Since joining from Northampton Saints in 2002, the 28-year-old has developed into a prolific try scorer - contributing 31 tries - and played a pivotal role in ensuring Edinburgh clinched second spot in the Magners League last season.
Now Webster, capped 37 times by Scotland, says he is determined to build on those achievements by fulfilling his potential over the next three seasons.
Webster said: "I'm really pleased to be staying at Edinburgh. I've been here for seven years, so by the time this new contract finishes I would have spent 10 years with the club.
"I love the city and the club; I feel really settled here. Edinburgh have just recorded our best ever finish in the Magners League and I genuinely believe we can progress further in order to challenge for trophies.
"I've enjoyed working with the coaches - they have certainly pushed me - and I still feel that I've got a lot of improvements to make; even though I've just turned 28.
"I look at players like Shane Williams, who is 32, and I've seen how he has performed over the past couple of years.
"There is so much more that I want to achieve as a player and I believe I can do that at Edinburgh."
During Edinburgh's record-breaking run-in, where the team chalked up six victories in a row, Webster contributed three tries which put him joint third on 28 in Celtic Rugby's all-time scoring chart.
Webster believes Edinburgh's expansive brand of rugby means that the team will always score tries; even if he doesn't cross the whitewash.
He added: "It is always nice to score tries, but I must admit it is not something I pay a great deal of attention towards. Certainly as a winger I'm more than happy to score tries.
"I think the brand of rugby Edinburgh plays always means we are going to score tries and the fact we finished the season scoring more points than the champions, Munster illustrates that.
"I certainly enjoyed the second half of the season after my injury in the 6 Nations."
Following last season's eye-catching feats, many seasoned observers have tipped Edinburgh to challenge for trophies, both in the Magners League and the Heineken Cup.
Webster stresses that while Edinburgh have made some real progress, the team must continue that same level of development in order to challenge with the upper echelons of northern hemisphere club rugby.
He said: "We have got strength in depth in the squad with young guys pushing for places.
"Guys know if they play badly then they won't get picked the following week. That is important for the coaches, but it is also important for the squad.
"The Heineken Cup will be a huge challenge when you look at the quality of the likes of Leinster, Munster, Cardiff and Ospreys.
"We have got to be better next year in order to compete with these teams because all the top clubs make improvements every season."
Webster has shown his commitment for the 2009/2010 campaign and now Edinburgh supporters are being encouraged to follow suit by signing up for a great value Season Ticket package.
Junior Season Tickets, for supporters under the age of 18, are available for only £30 which enables the supporter to enjoy 24 hours of top-class rugby action.
For more details, supporters are advised to visit the club's official website, edinburghrugby.org or to call the Scottish Rugby Ticket Centre on 0131 346 5180.
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