The first disc is the closest to the classic art song in style, allowing Anne Sofie von Otter to give full expression to these songs. Five are settings by Mehldau of poems by the early American poet Sara Teasdale, with one poem each from e.e. cummings and Philip Larkin. Von Otter invests these with plenty of rubato and emotion; this is her disc.

The second disc shows more freedom in a light pop-jazz way. Although von Otter confesses she dares not try improvisation, she is able to cope easily with Mehldau’s mildly swinging approach to standards by composers including Richard Rodgers, Joni Mitchell, Lennon-McCartney, Bernstein and a group of French masters of the genre, including Michel Legrand and Jacques Brel. She does this by mainly observing rhythm and melody and lightening up the intense interpretative expression we heard earlier. Lightness is the key.

It is a pleasant...