Alastair John Lyndhurst Bruce, 5th Baron Aberdare, KStJ DL (born 2 May 1947), is a British nobleman, and since 2009 a crossbench hereditary peer elected under the House of Lords Act 1999.

Lord Aberdare was born at 12 Avenue Road in St John's Wood, London,[1] the son of Morys Bruce, 4th Baron Aberdare, and Maud Helen Sarah Dashwood, only daughter of Sir John Dashwood, 10th Baronet.

A by-election took place under the terms of the House of Lords Act 1999, which provided for 92 hereditary peers to keep their seats in the reformed House, with vacancies in their number filled from amongst all non-sitting hereditary peers.

The result was announced in the Chamber of the Lords on 15 July 2009, following the voting by 27 of the 29 Crossbench peers eligible to take part.

[5] He married Elizabeth Mary Culbert Foulkes in 1971; they have two children: This biography of a baron in the peerage of the United Kingdom is a stub.