Plans are also afoot to expand the firm's premises, with building expected to begin at The Auction Centre early next year.
In the year of his 65th birthday, Rodney has assumed the role of chairman of the North Yorkshire firm that last year posted record January to December sales of £12m. He told ATG: "I find myself in the unique and fortunate position of passing on the traditions and values that were established by my grandfather to my three daughters, who this year have all been made directors of the business."
Alison, 29, has worked at The Auction Centre for five years (focused primarily on logistics and administration), while Jane, 25, who previously worked for interiors firm Oka, joined the firm at the beginning of this year and is already taking the rostrum for general sales. Caroline, 31, is a London-based accountant and will now contribute to financial planning.
In short, all will have a direct input into running a family firm that, with turnover figures consistently among the highest in the UK, has previously been linked with a number of potential suitors.
Jeremy Pattison, who joined the firm as a furniture specialist in 2004, has been appointed managing director while, after more than 25 years with the firm, Audrey Fall has become finance director.
Rodney told ATG he hoped the re-structuring "will provide the opportunity for me to leave the day-to-day running of the business to the next generation, allowing me the time to get out on the road and in the air visiting clients to advise on their collections, which is an aspect of the business I have always loved".
In contrast to the early days of the firm in the inter-War years - when Rodney's grandfather sold livestock and agricultural machinery from the towns and villages of North Yorkshire - many of the firm's clients are now based in the south of England.
To this effect, a final addition to the Tennants team is Marc Allum, who is joining as a valuer and consultant in London and the South of England. A well-known antiques writer and BBC Antiques Roadshow expert, the Wiltshire-based specialist is also an experienced auctioneer and general valuer after many years at Rosebery's.
Jane Tennant said the continued growth of the firm into specialist areas had prompted them to bring forward plans to create a new wing at The Auction Centre, the purpose-built venue just outside Leyburn, that has often been described as a model for the UK regional saleroom.
The architect's plans for a new building, to allow the venue to be used again for lectures and entertainment purposes, have yet to be finalised, but the firm are on schedule to start construction at the beginning of 2013.