Details of extant records on Archives Network Wales for the following;

• Record Office Business Survey Documents   "In 1977-1978, Carmarthenshire Record Office carried out a survey of businesses in Carmarthenshire, Cardiganshire and Pembrokeshire, producing synopses of their history and survey lists of their records."  
• Business Records, Pembrokeshire  1736-1989      "Pembrokeshire Record Office has collected the records of numerous businesses in Pembrokeshire...................."

• TNA provide:
  • A very useful  Research Guide: Companies and business
  • Their National Register of Archives (NRA) ("Discovery") is particularly useful for finding the location of the archived records of named organisations
• The Association of Business Historians creates and disseminates knowledge about business history.
• TNA hold some railway company records. (Ancestry provides subscription access to the TNA's railway employment records 1833-1958, from a number of historic railway companies.)
• Some employers' and trade association archives are held by Warwick University's Modern Record Centre.
• Trade directories can provide some information (including advertisements) about businesses, large and small, through the years.
• Railway Work, Life and Death - records of railway worker accidents in Britain between 1911 and 1915 - "a joint initiative between the University of Portsmouth and the National Railway Museum (NRM)".
• The John Lewis Memory Store: ". . . a living history of John Lewis & Partners. Through the site, people share their memories, photos, maps and information about John Lewis & Partners, past and present."
• United Kingdom Cemetery Records, from Interment.net.