Maria Miller, minister for women and equalities should be standing up for older women in the UK.

There is a new generation of active older women who have led very different lives from their mothers. Now in their 50s and 60s, they are the first generation of women to have been 'doing it all'. They have worked, as well as bringing up children. They've got educational qualifications and then when their children leave home, these women regard themselves as being into their stride and in their prime.

But suddenly they are told, sorry you're too old. They represent a new generation of older women who don't fancy the idea that they are written off and regarded as past it because they are past 60.

It is clear there is quite an angry movement of older women out there so we have set up a Commission on Older Women. It is time public policy caught up to properly understand the lives of women in their fifties and sixties, and to better reflect their experiences and expectations. The lack of value placed on the wisdom and experience of older women is exemplified by the lack of older women on TV. What does it say to the many older women viewers when older women 'disappear' from our screens when they hit 50?

At last we see many young women blazing a trail in the media but when they reach their fifties they disappear. Broadcasters must own up to what's going on and confront a reality we all know is there. This dual discrimination of ageism and sexism is entrenched across the whole of the broadcasting industry and we're calling time on it. In a letter to broadcasters I have asked them to publish the number of older women working in their organisations, both on and off-screen.

Broadcasters rightly value the wisdom, expertise and authority of older male broadcasters but should be valuing their women broadcasters in the same way. The problem is not that there aren't older women around; the problem is once they get older they're shuffled off and disappear.

Broadcasters have to recognise that in the 21st century it's no longer acceptable to discriminate. They should be making sure the talent, which is both men and women, finds its way into the broadcasting industry and within the industry is treated fairly.

And Maria Miller, minister for women and equalities, should be standing up for all women, including older women. It is shameful that whilst there is a clause in the Equality Act 2010 which would allow (for example) older women to bring claims where they have been discriminated against on both sex and age grounds, the government has decided that they will not be bringing it into force. They've ditched this law just when women need it.

Discrimination against older women not only affects those whose careers are cut short but also, both the economy and public life lose out as a result. There has been a lot of change over the last few decades but there needs to be more, especially in relation to this pernicious dual discrimination of ageism and sexism.

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