Classical Music: State of the Nation South Bank Centre, London

It sounds a good title for a rock group - or a piece. No doubt the London Sinfonietta and its co-organisers - BBC Radio 3, COMA (Contemporary Music Making for Amateurs), SPNM (Society for the Promotion of New Music), Sonic Arts Network and Sound Intermedia Jukebox - didn't mean it too seriously. This was two days of concerts, workshops and discussions celebrating "the healthy state of composing in this country among the younger generations".

The chief showcase concert was given by the Sinfonietta under Paul Daniel at the Queen Elizabeth Hall on Saturday evening. John Lunn's and Karen Markham's advertised commissions weren't ready, as is sometimes the way with these things, so Richard Causton's The Persistence of Memory, already heard in London early last year, was substituted, a dreamlike fantasy of delights and horrors. More appealing, anyway, than Keith Johnson's Sabotage, whose title refers to its habit of nipping continuity in the bud (a bit of a contemporary affliction).

David Sawer's Tiroirs effects continuity in the manner of Chinese Whispers, and the sections seemed to run themselves, as if flicked by the composer's finger into automatic action. An intriguing, jumpy beginning, some elegant sonorities, but by Sawer's high standards, set beside his Trumpet Concerto or The Memory of Water, a less than consequential total shape, at least on a first hearing.

Philip Cashian's Chamber Concerto, originally written for the Birmingham Contemporary Music Group (and here receiving its London premiere), was fast and furious, successfully stitched together from many short sections, full of striking motifs purposefully directed. There was a lot of groovy chorusing of instruments in parallel and some nice dusky harmonies. It ended like slow irregular breathing. A strong close to the concert.

Earlier in the day, Thomas Ades's lunch-time piano recital included his own Darkness Visible - a distortion job on John Dowland - and pieces by five of his fellow twentysomethings. It's unfair, perhaps, to say that Julian Anderson's Etudes and Edward Dudley Hughes's Orchid gave most pleasure, since they began the programme, and as it wore on, the ear got tired and the music seemed splashier, pitches less important. Which reflects on the insufficiently contrasted choice of styles, though the last piece, Gladys by Jane Mielniczek, would have sounded monochrome anyway, even though it had a clear and coherent plan of textures.

On Sunday afternoon at the QEH, the London Sinfonietta, now under Markus Stenz, offered two works selected by the SPNM, both of which - fortuitously, surely - were beaty and hip. Sal's Sax, by Joe Cutler, could hardly fail to have effective moments, with an instrumental line-up that included three grand pianos, three saxophones and two electric guitars. Its sections were sharply defined but went on too long, or seemed to, because the basic ideas were plain and impersonal. Sam Hayden's Time Is Money, with only two grand pianos in the ensemble, lived up to its worldly-wise, right- on title as another child-of-Louis-Andriessen. Surely there are enough of those already? Between, from another world and generation, came Alma Bethany's stars, seas; chasms, inspired by the birth of her grandson. It set brief Christian phrases in Latin and words by William Blake, for a stratospheric soprano (Nicole Tibbels) and sizeable mixed ensemble that was sometimes deliberately dwarfed by a powerful tape extending the soprano's range, swamping her with janglings and sounds of the sea. It was ambitious, strongly expressive of personal feeling, including the pain of labour, but, perhaps inevitably, because of Bethany's limited experience as a composer, reliant on models.

After the interval, there was a sort of celebrity spot taken over by the delightful Django Bates, whose quartet Human Chain bubbled in Bates's Food for Plankton, and then joined the Sinfonietta in the first UK performances of his set of three pieces, Some More Upsets, which introduced a welcome mood of easy-going humour, including unusually conceived waltzes - a mournful one for a swan in a polluted landscape, and a quick brass-band number in homage to Raoul Dufy, who did all those sketchy paintings of race-courses.