Perched on a stool in a crisp dress shirt fastened with studs and with a nylon-strung instrument of contemporary design round his neck, guitarist Nigel Clark looked poised to impress. He did too, with a beautifully selected and fluently executed set of tunes that ran the gamut from his own compositions to the work of Jimmy Van Heusen and Carlos Santana's Samba Pa Ti. It was a very agreeable hour in his company and the Ramshorn Theatre was full to capacity to hear it. Alongside a couple of us press bods there were a good few others there on a specific mission, beyond taking in some fine lunchtime jazz. Identifiable by the red lanyards suspending laminate passes round their necks, they were the delegates to Homegrown, the weekend's showcase of Scottish jazz talent as part of Glasgow Jazz Festival.

The full house for Clark, once a member of pop group Hue and Cry's ensemble (an experience which would also be recollected by saxophonist Tommy Smith later in the weekend) and most recently a crucial presence in Hilary Brooks's pit-band for Dundee Rep's Proclaimers musical Sunshine on Leith, was the first intimation I had that something special was happening in the city. Clark was delighted, if a little taken aback, by the size of his audience ("Has it started raining?" he asked), but that turned out to be the norm for every event. Even at 11am, 350 people had turned up to hear the young apprentices in Tommy Smith's Youth Jazz Orchestra show what they could do in the Old Fruitmarket. Gig after gig in the Ramshorn and the City Halls was filled to capacity. It was a phenomenon that caused some headaches for festival director Jill Rodger and her colleagues, with public enthusiasm putting pressure on space for those delegates, but it was a problem they were happy to have to deal with.

The delegates to Homegrown are the sort of promoters, funders and recording companies who are in a position to further the careers of Scotland's jazz musicians, and they were impressed. Their number included not just bookers from clubs like Ronnie Scotts and directors of festivals in England but a group of office-bearers from the Europe Jazz Network, who converged on the city for the festival and to have a planning meeting for the organisation's General Assembly, which will be held in Glasgow for the first time at the end of September. Appropriately, and on the evidence of what they saw, the EJN has decided to invite the Glasgow Jazz Festival into its inner circle as one of the continent's elite events.

Of course it wasn't just the fantastic attendances that impressed the EJN committee - although that must have helped - but the effort that had been made by the musicians. Homegrown is programmed by agent (and jazz singer) Cathie Rae and each band or artiste is allowed a strict hour to make a mark, a discipline that does not come naturally to the often relaxed time-keeping of jazz musicians. Clark, for example, had carefully researched anecdotes to go with all of his music. His performance was like one of these informative BBC Radio 2 shows that delve into the stories behind the songs.

From that point of view, his was probably the most polished presentation of those I managed to catch, but every band made a conspicuous effort to step beyond the usual perfunctory introduction of those on stage and engage with the audience.

So, as well as the music, I will remember the proportionate level of grief that bassist Mario Caribe implied, when he told how the loss of a family pet was the genesis for the playful-sounding Dead Cat Blues, as well as the confession of pianist Steve Hamilton that a composition dedicated to his sister (present in the second-front row) had led to pressure from his family - because he has two other sisters.

At least 10 acts featured in this year's Homegrown and each evening culminated in a sell-out big band performance in the Old Fruitmarket featuring those same Scottish-based musicians and their colleagues (see review below). After some difficult years and at a time when financial support from all sources is hard to find, this year's Glasgow Jazz Festival has shown the music to be in popular good health, with local musicians, once thought the poor relations, making up a huge proportion of the strength of the programme. Glasgow Jazz Festival ends with an exclusive solo concert by pianist Chick Corea at the O2 Academy tonight.