Men may have to move aside from high-profile roles in business and government to make way for women to move in, according to the chairman of Transfield, Diane Smith-Gander.

A bill proposed by a group of Senate crossbenchers would make it compulsory for federal government boards to be at least 40 per cent female.

Transfield has responded to activists' claims transparently and accurately, Smith-Gander says. Credit:James Brickwood

Ms Smith-Gander, who is also president of the Chief Executive Women group, said to reach that target, and an eventual bigger target of 50-50 representation of women on business boards and in senior roles, capable men would have to make way for capable women.

"When it comes to senior jobs and political appointments I think 50-50 representation is where we're heading," she said at an Australian Institute of Company Directors lunch in Melbourne on Tuesday.