Birse's transformation from a contractor with a reputation for playing hard to a new-age business has attracted a huge amount of publicity.
In June 1997, the chairman publicly apologised for having been too aggressive towards clients in the past and for upsetting employees.
Birse then introduced a non-confrontational culture at the company, bringing in a "resources consultancy" to train staff in the new approach.
And last year, the company made national headlines when it bombarded a Welsh local authority with fairies, toadstools and faxes containing the thoughts of Nelson Mandela in a bizarre attempt to settle an outstanding £11.5m bill. The bid failed, and Birse is still in arbitration with the council involved.
Birse said he did not regret the changes, as they had helped staff face up to difficult issues.
"On the whole, it's been good for Birse. Internal communications have been improved. We can deal with situations a lot better than we used to.
"I think there's a much better atmosphere in the company. If we could start making money now, we would be on a high." Birse made it clear that the company was still a tough commercial organisation despite the changes.
"A lot of people thought that, with our culture change, we were nice people who couldn't make staff redundant. We couldn't be like that. If we were, we would go bust."