Kirsty Young's castaway this week is Dame Eliza Manningham-Buller. She has recently stepped down as Britain's top spy-master - or more correctly, the Director-General of MI5. She took the helm in the months after the attacks of 11th September 2001 in America and steered the service through a time when the nature of the terrorist threat facing Britain changed enormously and new measures were introduced to counteract it.

She concedes that MI5 has to rely, in large part, on information that is 'patchy and incomplete' and that ultimately the service will always be judged 'by what we do not know and did not prevent'. In her first ever interview, Dame Eliza talks gives her recollections about the day when Britain was targeted by suicide bombers, describes what lay behind her own departure from the service and reveals how her mother's role during World War II fuelled her own interest in public service.

[Taken from the original programme material for this archive edition of Desert Island Discs]

Favourite track: The opening of String Quintet in C by Franz Schubert