Calling all budget holders: if your creative agency is still turning up to meetings with an unevolved cast of characters, that doesn't represent you, or your customers, or indeed any kind of real life demographics... Syl Saller, Chief Marketing Officer of Diageo, has just thrown down the gauntlet for you.

Apparently, she has personally written to all of the advertising and media agencies on Diageo's roster asking them to report back to her on their status on female agency leadership, female creative leadership, and what their gender pay gap is like.

She is in a powerful position as a decision maker and budget holder (£1.8bn in ad spend, according to The Drum), with the influence to make agencies listen. I find an outside intervention like this one most welcome, as an agency lead looking around for my female industry peers.

Saller hasn't said that's what she'll do with the information; she left it open exactly what consequences there will be for agencies lacking any initiative to put the balance straight. But as a Diageo partner in the employer brand space, as the female Executive Creative Director, and as a member of a 50/50 gender-balanced Management Team -- my team at TMP and its methods stand ready for inspection. (And improvement, if you have any suggestions!)

The business case for inclusion is clear: organisations with higher diversity at a senior level are proven to have a better financial bottom line. But this data doesn't seem to be enough for a lot of agencies. Until inequality costs a business something concrete -- a potential partnership with an exciting global business like Diageo for example -- they can be reluctant to change the formula.

Women are just as capable as men are to be inspiring creatives, strong leaders and effective voices on a board. Saller told The Drum,  “We want to know why there aren't more women creative directors; there’s a variety of answers but that’s one of the last bastions we need to understand.”

I'm not saying I understand all those reasons, but here are some of the things you can do about it internally:

- Reward female talent. Have a transparent pay policy. If yours isn't, ask the person in charge of setting policy why it isn't. Pay women fairly for their work whether they've 'fought' for it or not. Promote women. And if you worry that none of your women seem ready to promote, ask yourself why not? What are you not doing as employer to nurture their leadership skills? Invest in putting it straight. 

- Become mindful of bias. Do unconscious bias training. Make everyone attend, including the C-suite. In fact, get the C-suite to sponsor it personally. Be very thoughtful about your leadership framework if you have one, or just your 'sense' of what a leader looks like. Ban all male shortlists. Ban all male interview panels. 

- Be flexible. With just 2% of men in the UK taking up shared parental leave, women still disproportionately bear the responsibility for caring for children. Offer flexible options to keep people (particularly women) in the workforce. Check to see whether your parental leave policy offers women and men the same benefits. If it doesn't, ask difficult questions of important people. 

- Create solidarity. TMP has a women's network that provides advice, information sharing and social events designed to build confidence among colleagues, alumni and freelance partners. It doesn't take more than 2 minutes to set up a Facebook group or Yammer group or Slack channel or email list that opens up a channel of communication for women. Don't ask your boss; this operates outside traditional power structures. Proceed until apprehended.

- Share your expertise. Already good at this? We regularly do speaking events and workshops to share best practice for gender equality and other areas of inclusion and you can too. All you need is a room and some snacks and some people ready to compare experiences. Give yourself permission to share, even before you're perfect. Because you never will be.