It's more than 20 years since Lesley MacDonagh did it. Glass ceiling shattered – the first woman to become managing partner of a top 10 City firm, ran the Law Society Gazette headline. Celebrating her appointment, Legal Business followed up with a suitably stylish cover.

Over the next decade, MacDonagh excelled. As managing partner of Lovell White Durrant (the UK predecessor of transatlantic powerhouse Hogan Lovells), she held the position uncontested for three terms: overseeing the firm's growth, doubling its lawyer headcount to more than 1600, completing several mergers, and taking the total number of offices to 27 worldwide.

In the wake of MacDonagh's success, others soon followed, not least employment law guru Janet Gaymer, now Dame Janet, who became senior partner at Simmons & Simmons. Today, there are several outstanding female managing partners in top firms on both sides of the Atlantic. It has become the new normal.

But not among the five London-based law firms that comprise the magic circle: Allen & Overy, Clifford Chance, Freshfields Bruckhaus Deringer, Linklaters, and Slaughter and May.

As Allen & Overy announced this week the names of eight partners hoping to succeed the retiring managing partner, Wim Dejonghe and senior partner, David Morley, there was not one woman on either shortlist (of four) for each position.

If a woman can successfully run Europe's biggest economy, then why not one of Europe's biggest law firms?

It was the same story a few months ago at Linklaters when the Silk Street communications team announced a six-man shortlist to replace Simon Davies as managing partner.

Go back a decade to when the great (Sir) Anthony Salz stood down as co-senior partner at Freshfields: another all male shortlist of six emerged.

The same pattern was repeated at Freshfields this year, when only men contested the senior and co-managing partner vacancies, while the only woman partner tipped for the job, Caroline Stroud, decided not to run.

It's been a similar story too over the years at Clifford Chance, most recently when Matthew Layton replaced David Childs as managing partner.

In his exit interview with the FT in November 2013, Childs expressed disappointment that there were too few women partners at Clifford Chance, and none on the management committee. Despite setting a target in 2008 of women forming 30% of the worldwide partnership, it languished at 15.3%.

"It's not good enough," Childs said. "It's disappointing."

So what about a woman in charge of Slaughter and May? Urbane and genial, Chris Saul steps down as senior partner next June. He works closely with the firm's practice and executive partners: no position in this triumvirate has ever been held by a woman. But will the conservative firm break the mould?

I decided to ask a respected Slaughters' partner over dinner. "Not during my time left at the firm," came his Delphic response. In pursuing the point further, his logic was not driven by any hint of sexism, more by a perceived lack of desire among his female cohort: although there are very able women partners at the firm, he argued, none of them would want the job.

This week, I chatted to a female partner at A&O, and asked her the same questions. There are women who could do it, but they don't want to, she concurred. Why? I asked. Too busy with their work, and no great ambition to be in the spotlight, she suggested, explaining that there had been moves to push one woman onto the shortlist, but she eventually baulked at it.

For the magic circle firm that eventually does have a woman, or even women, on their managing partner shortlist, it will be a bold step. And for the first of their number that actually appoints a woman as managing partner, it will potentially make the biggest contribution to gender diversity among City law firms so far this century.

After all, if a woman can successfully run Europe's biggest economy, then why not one of Europe's biggest law firms?

But at the rate things are moving, don't hold your breath.