Publishers
- Andrew Spottiswoode 1
- Andrews & Co. 1
- Angler's Mail 1
- Angus & Robertson 10
- Angus & Robertson Ltd. 3
- Angus & Robertson Publishers 7
- Annual Concepts Limited 8
- Annual Reviews Inc. 1
- Anstalt 1
- Ant Belmont 1
- Anthony Blond 2
- Anthony Nelson Ltd. 2
- Anthony Treherne & Co. Ltd. 1
- Antique Collectors' Club 8
- Antonio Delfino Editore 1
- Antony Atha 1
- Anuart Ediciones 1
- Ap Natural World 1
- Apach Publishing 1
- Apecs Press 2
- Apple Press 1
- Apple Tree Press 1
- Appletree Press 1
- Applied Science Publishers Ltd. 4
- Apress 1
- April Cottage Publications 1
- Aquarian Thorsons 1
- Arabesque 1
- Arandar Books Ltd. 2
- Arbeit Munich 1
- Arcadia 5
- Arch 1
- Archaeologia Cambrensis 1
- Archaeopress 2
- Archangel Press 2
- Archibald Constable & Co. Ltd. 7
- Archibald Constable And Co. 2
- Archibald Constable And Company 1
- Architectural And Archaeological Society Of Durham And Northumberland 1
- Archon Books 3
- Arco 1
- Arco Publications 2
- Arco Publishing 5
- Arcos Verlag 1
- Arctic Fox Books 1
- Argosy-Antiquarian Ltd. 1
- Argraffdy'R Methodistiaid Calfinaidd 1
- Argus Books 2
- Argyll Publishing 2
- Arkstee & Merkus 1
- Arlequin Press 1
- Arlington Books 3
- Armada 25
- Arman Enterprises, Inc. 1
- Arms & Armour Press 35
- Arnold 3
- Arrow Publishing 1
- Arrowsmith 2
- Art & Educational Publishers Limited 3
- Art & Humour Publishing Co. 1
- Art & Humour Publishing Co. Ltd. 1
- Art And Educational Publishers Ltd. 1
- Art Books International 1
- Art Gallery Of Alberta 1
- Art Revisited 1
- Art Services International 2
- Artabras 2
- Artech House 1
- Arthur A. Levine 2
- Arthur Ackermann 1
- Arthur Barker Limited 9
- Arthur Barker Ltd. 7
- Arthur Barron Ltd. 2
- Arthur H. Stockwell Ltd. 6
- Arthur L. Humphreys 1
- Arthur Wigley & Sons Ltd. 1
- Arti Grafiche Gajani 1
- Arti Grafiche Saturnia 1
- Artia 1
- Artima 1
- Artis-Historia Publishing 1
- Arts and General Publishers Ltd. 1
- Artur Wolf 2
- Ascherberg, Hopwood & Crew Ltd. 2
- Ashford 1
- Ashford Press Publishing 2
- Ashgate 3
- Ashgate Publishing Company 2
- Ashgrove Press 1
- Ashley James Limited 1
- Ashridge Press 1
- Asia Publishing House 1
- Aslib 2
- Aspect Corp. 1
- Aspect Publishing 1
- Associacio Per A La Defensa De La Natura 1
- Associated Newspapers 3
- Associated Newspapers Ltd. 4
- Association Of Family History Societies Of Wales 1
- Aston Martin 1