Editor’s Note: Out this month is Lib Dem MP Jo Swinson’s book Equal Power. Here she writes about the battle for equality and you can get her new book yourself from Amazon, Hive or The Guardian bookshop.

With rampant sexual harassment at a corporate charity dinner, the BBC accused of breaking equal pay law, and Easyjet’s new male CEO admitting he was offered £34,000 more to do the same job as his female predecessor, you don’t need to look far to find gender inequality in the news. And that’s just stories from one week.

When I was the Liberal Democrat Minister for Women, I learned that many seemingly different issues – the gender pay gap, violence against women, workplace discrimination, body image, division of caring responsibilities, gender stereotypes, women’s under-representation in politics – are all different parts of the same fiendishly difficult jigsaw. Tackling the problem of gender inequality means chipping away at all of these issues simultaneously because together they reinforce the entrenched power imbalance between men and women.

The backlash in the letters page of the Financial Times last week showed what we’re up against, as writers bemoaned the FT even covering the issue of sexual harassment, and referred to the women groped in their workplace as “silly young girls”. When I spoke out on television – albeit colourfully – against the everyday sexism and misogyny that sees schoolgirls sexually harassed, I was called a “little missy”.

It should be a core mission for us as liberals to challenge concentrations of power, including the power hoarded in the hands of rich, white men.

Gendered assumptions are everywhere. While women bear the brunt of these injustices, rigid cultural expectations about gender also harm men, not least in terms of their mental health. Men are also undervalued in their role as fathers, something I started trying to change with the introduction of shared parental leave.

Our party is not immune to the sexism that permeates through every part of society, but we can all act – individually and collectively – to be part of the solution. We need to recognise the nature of the problem: it is structural and ingrained in each and every one of us, absorbed from the surrounding culture. Changing it takes constant attention and proactive effort. Wringing our hands or shrugging our shoulders when few women ‘come forward’ won’t cut it for our party in 2018.

We need to count women – on our membership lists, on local party committees, in our Council groups, on the conference platform – and reach out to rectify imbalances. Ask her to join the party. Ask her to be on the committee. Ask her to stand for election. Don’t ask her to sort out the catering while the men plan the campaign. Our benchmark needs to be 50:50, not simply better than before.

The most important thing is to take action – and we can all do something. Equal Power contains dozens of ideas for things you can do, from changing a conversation to launching a campaign. Together we can create a more gender equal world in politics and beyond.

* Jo Swinson is Liberal Democrat MP for East Dunbartonshire, and was a Minister in the Department for Business, Innovation and Skills and Equalities Minister from 2012-15.