Gabion: Welsh Phoenix: The Wales Millennium Centre 2/2

Like a football manager buying in a top player, the practice signed up the architect Jonathan Adams, who had worked for some years with the highly original and internationally-known architect Will Alsop - presently battling with Sir Norman Foster to win the commission for the London Assembly building. Adams is Welsh, indeed was born near Cardiff. He had helped design Alsop's celebrated Cardiff Bay visitor centre, an oval tube of a building that is still one of the best new things on the waterfront. Adams has personally scraped lugworms off it. Alsop's practice is also involved on the barrage project, so Adams' professional links with Cardiff are strong. He understands the local climate, both politically and meteorologically. And the Mark 2 Wales Millennium Centre is his work.

As with all the best buildings, it has one basic good idea. This is to wrap the auditorium and flytower up in one burnished metal form, somewhat like the hull of a ship, and to set that upon a geologically-inspired plinth of other accommodation, made of inward-leaning walls of roughly-layered slate interwoven with veins of thick, solid glass. Adams knows how it will go together. When we meet, he drives me out to a wasteland on the edge of town where, in a big white tent, he has built a test wall of his chosen materials to show any doubting Thomases. His scheme has been submitted for planning approval. After the controversy surrounding Hadid's project, he is leaving little to chance.

Jonathan Adams of PTP: Wales Millennium Centre

Adams is enthusiastic and wholly serious about his project - which is fully funded, and needs only the planning decision to go. He responds with a straight bat when I suggest he might be over-egging the Welshness of his design - what with the Welsh script spelling out the name of the centre being cut out of the foyer wall over the entrance - each letter so huge as to make a window. Or the extensive use of Welsh hardwoods in the interior, where the cast-iron columns will be based on the tree-ferns of ancient times found in fossil forms in the South Wales coal seams. Or for that matter the references to the stratified local cliffs, and the steel-making and shipbuilding industries. Gently, Adams suggests that the new building has to be seen as emerging from Wales - by which he presumably means that the previous opera house here was seen as an interloper.

As Tony Blair has discovered, the Welsh are not at all keen on imposed candidates from London or elsewhere. And whereas Patrick Davies's very prominent new hotel is deemed permissible as a commercial variant of expressive international modernism - it's an inward investment, really, like all the Japanese factories round here - the public buildings are a different matter entirely, and are seen as an expression of national identity.

For this reason, Richard Rogers still has plenty of hurdles to overcome with his Welsh Assembly design. Call this attitude parochial if you like (I certainly have in the past), but you ignore it at your peril. Adams, back from his spell working for an international practice in London, has an instinctive understanding of, and affection for, the Welsh-centred outlook.

He has succeeded aesthetically at least. I like the idea of being able to see right through the building down an internal street where scenery moves to and from the stage, for instance, and the undulating gallery fronts overlooking the main public concourse promise excitement. It remains to be seen how well the auditorium will work acoustically. It is to be a multi-use hall, with adjustable acoustics, and experience suggests that multi-purpose halls are never quite so good as those fully dedicated to opera, orchestral concerts, musicals, drama or whatever. Normally one mode dominates in a multi-use hall: here Adams has worked with both WNO and the Cameron Mackintosh organisation in an attempt to reconcile the differing demands of opera and musicals. There is no doubt, however, that an important cultural building is needed here, next door to the new Welsh Assembly, concluding a new boulevard, Bute Avenue, which will run up to the city centre. Adams has risen to the challenge. Against the odds, it looks as if a good and distinctive building will rise from the squelchy mud of the Cardiff Bay Opera House affair. But, hang on, this is Wales: best not to count your lugworms before they're dispatched.