They were written over a period of more than twenty-five years, the first a few years after her suicide in 1963, and represent Ted Hughes's only account of his relationship with Plath and of the psychological drama that led both to the writing of her greatest poems and to her death. The book became an instant bestseller on its publication in 1998 and won the Forward Prize for Poetry in the same year.

'To read Birthday Letters is to experience the psychic equivalent of "the bends". It takes you down to levels of pressure where the undertruths of sadness and endurance leave you gasping.' Seamus Heaney

'Even if it were possible to set aside its biographical value . . . its linguistic, technical and imaginative feats would guarantee its future. Hughes is one of the most important poets of the century and this is his greatest book.' Andrew Motion