Solar and Lichtbogen are fine examples of Kaija Saariaho's ability to create richly textured tapestries of orchestral colour. Solar is about brilliant colour, from a tangled clamour of bright sounds to luminous motionlessness, with a central section of florid solo lines. Lichtbogen (literally 'arc') was suggested by the Northern Lights; the colour here is more shimmering, subtly modulated by a most beguiling use of live electronics not so much to transform the instrumental sounds as to extend their palettes. In both cases it is hard to believe that only a chamber group is involved, of 12 and seven players respectively.

Admirers of Saariaho's music will perhaps be disappointed to find that the only way of acquiring these accomplished and poetic pieces is by buying a second recording of her violin concerto Graal théâtre, which many will already have in the splendid recording by Gidon Kremer. But that isn't quite the case. Two years after writing Graal théâtre Saariaho produced an alternative version using a chamber ensemble of 18 players. The solo line is unchanged, many passages are in any case sparingly scored, and the newer version remains a concerto, with no lack of 'orchestral' weight of tone. But the relationships between the soloist and the other players are inevitably different and in this performance one is slightly more often reminded than by Kremer that the marking of the long first movement is 'delicato'. John Storgårds has all the technique for this love-letter to the violin's expressive and virtuosic nature, but on the reasonable assumption that most people will only want one recording of Graal théâtre it would have to be Kremer's, because the couplings (the exquisite song-sequence Château de l'âme and the cello concerto Amers) are even more desirable than those offered here; in the case of the violin concerto, though, it is a close-run contest.

Saariaho's Flute Concerto is beautiful and characteristically imaginative, an extended study of the flight and the movement of birds but also a very striking re-thinking of the idea of 'concerto'. At the beginning the flute almost designs the orchestra, generating not only melodic ideas but timbres; in a later section (a brilliant virtuoso dance-scherzo) the soloist 'teaches' the orchestra the melodic and other ideas that this vividly coloured movement uses. Other instruments take flight and become kindred birds, the space between a hovering bird and its shadow on the motionless earth beneath is finely suggested, but this is no mere imitative piece. It is at the same time a meditation on the symbolism of birds suggested by the poems of Saint-John Perse, to whose imaginative world the solo flute piece Laconisme de l'aile, written at the very beginning of Saariaho's mature career, is also indebted. Indeed in that piece the sounds of the flute, including multiphonics and other techniques, are generated by Perse's words, intoned by the flautist at the outset.

The Montaigne disc is turned into an hommage to Perse by the inclusion of six of his poems, read in French by the writer Amin Maalouf and in English translation by the (American) flautist Camilla Hoitenga. Each poem is equipped with a 'sonic environment' composed by Saariaho using fragments of birdsong and flute phrases manipulated by computer. This material fills rather more than half the disc, but I cannot imagine wanting to hear it nearly so often as the Flute Concerto and its 'ancestor'. That Concerto, though, in its combination of richness of material, poetic imagery and strong dramatic structure, is one of Saariaho's major achievements. It is splendidly played and both cleanly and spaciously recorded.