When they arrive in their offices tomorrow the chairmen, heads of board committees and company secretaries of the UK's biggest 350 listed companies will find a 20-page document on their desks.

Rearranging the chairs, by headhunter Bird & Co, promises to be "A blueprint for the next generation of board leadership." This is a detailed critique of the failure of British business to properly train and promote a diverse range of chairmen, which means it takes a good look at why there are only eight women, including those pictured, who hold this role in the FTSE 350.

Of the 10 key recommendations to boost that membership, the last is perhaps the most significant: "More adventurous sourcing should be encouraged. Boards should embrace the idea of 'younger, female, different' early in discussion and get comfortable with it."

After speaking to 50 chairmen and non-executives about their jobs and their routes to reaching those positions, Bird & Co founding partner Isabel Bird found that "the executive journey for women is fundamentally different than it is for men".

This can be the result of women being less confident to push themselves forward; a stalled career as many are still expected, or want, to be the "primary care takers" of their children, leaving them maybe five years behind their male colleagues; or the desire to retire slightly younger than the guys who still want to hold on to major jobs well into their sixties.

As the experiences of the panel, right, shows, there's no obvious structure to help women overcome these obstacles. As a result, few even reach board level, meaning that, as Bird puts it, the reason for not getting a chairman's role becomes one of "supply as much as demand".

Alison Carnwath is the only chairwoman in the FTSE 100 index of biggest British companies, having held the job at property giant Land Securities since late 2008.

While she doesn't recognise herself as having less confidence than the men around her ("I've never been afraid to express my opinions") nor that children are a problem ("We live in an era of flexible working, give and take"), Carnwath does believe it's difficult for women to take that first major step of getting onto the non-executive board itself.

A successful investment banker at Schroders in the late Nineties, Carnwath got her first board role at mid-cap company Vitec. The broadcast equipment group was a long-standing client, meaning she had "a pre-existing relationship, they knew me and I knew them, which resulted in me being invited on to the board".

Carnwath didn't exactly get lucky, but she was in a different position to many women of her age. She says that since that first board position was bagged she never experienced any problems getting other roles as a result of her gender.

Asked whether she is for or against Lord Davies' target for 25 per cent of board members to be women by 2015, Carnwath sighs: "We've moved beyond the pro or against point. The reality is that things were moving so slowly that inevitably targets were going to come in at some point. But there's no real evidence to suggest women being on a board makes the companies any better – what we're doing here is forcing an experiment."

While Bird's report calls for mentoring schemes to bring along potential chairmen with wider range of backgrounds as well as improved board review processes, there is a sense that there is now an onus on women to take advantage of the changing attitude towards gender.

Colette Bowe, who chairs Electra Private Equity, says headhunters have become "very good indeed at identifying women candidates over the past five to 10 years".

Clodagh Hayes, a corporate partner at "magic circle" law firm Linklaters, has looked closely at the issue. She argues: "There needs to be a change of mindset so that other people outside of [an appointment panel] should consider people beyond their narrow field of vision. At the same time, it is up to women to push themselves and not wait around for people to put them forward."

Should they need an inspiration of what such self-confidence can achieve, such candidates need only look at Victrex chairwoman Anita Frew. She smiles: "Don't laugh, but as I was growing up, I knew I wanted to be a board director by the time I was 40. The annual meeting confirming my directorship was held on my 40th birthday and I was a chairman when I was 50."

Not all potential chairmen, of either sex, have their career paths so well mapped-out. Perhaps they, too, should try and develop such purpose of vision.

Anita Frew, Victrex

The woman with the plan might not have the same ring to it as the masculine equivalent, but a plan Frew stuck to. As a child, Frew wanted to be a director by 40, which she achieved to the very day and the 55-year-old has been a UK boardroom fixture ever since

Karin Forseke,

Alliance Trust

The Dundee-based investment company maybe an old company at 124-years-old, but it is anextremely 21st century-looking institution as both its chair and chief executive, Katherine Garrett-Cox, are women. Forseke, a Swede who was once deputy chairman at the Financial Services Authority, even succeeded a woman, Lesley Knox

Alison Carnwath, Land Securities

The former investment banker has developed a portfolio career to equal almost any of her male peers, having also served at Barclays and Friends Provident. Carnwath got her first board role at a company that recognised her strengths while it was a client

Dame Helen Alexander, UBM

Already a City bigwig as a former president of the Confederation of British Industry, Alexander was well known in media circles for chairing privately-owned business-to-business magazine publisher Incisive Media. This made her an obvious choice when Building and Property week publisher UBM went hunting for a new chair this year

Colette Bowe, Electra Private Equity