Unions fear the internal market programme, which is intended - 12 years after privatisation - to sweep away the last traces of civil service culture, could lead to whole chunks of the company's operations being hived off if they fail to meet exacting performance targets.
Project leader Jeff Richardson said BT hoped to avoid "mistakes" that the BBC had made by introducing the changes gradually.
"This won't be a big bang. The aim is to be evolutionary rather than revolutionary."Reuse content