A merger between French Duncan and Sterling-based Macfarlane Gray will lead to one of the largest mid-tier accountancy practices in Scotland.
The combined fee income of the amalgamation will be £10m, with 200 employees spread out across eight Scottish offices.
Founded in 1934, with a current turnover of £2m, Macfarlane Gray was recently awarded ACCA's best British independent firm of 2012 title and will retain its name under the terms agreed in the merger.
French Duncan chairman Robert Kerr said: 'French Duncan has seen dramatic changes in the last 18 months with the recruitment of a plethora of new talent, including a number of new partner appointments from our larger competitors.
'I think it's fair to say that, at the moment, we are one of the most focused and dynamic practices in Scotland and the merger with Macfarlane Gray is just one more step on the road to our goal of becoming Scotland's premier indigenous accountancy practice. I would also say that, while some of our competitors are talking about mergers, we're actually doing it.'
Macfarlane Gray principal, Greg Callan added: 'It represents a great example of two plus two equaling way more than four! Macfarlane Gray will play a major role in the strategy of the combined business and we share a common approach to assisting our clients develop and grow.'