The Oxford English Dictionary defines a role model as "a person regarded by others as an example to be imitated."
However, it seems to me that the most exceptional role models do much more than set a good example. We have all been inspired by successful people in the public eye, but the best role models are usually relatives, friends or teachers who believe in us and help us fulfil our potential.
Today's young people - almost a million of whom are unemployed - need good role models more than ever. They need to be inspired by people who have overcome barriers to achieve success, but more importantly, they need support from people who are willing to pass on what they've learnt to the next generation.
Sadly, thousands of the young people we help at The Prince's Trust do not grow up surrounded by positive role models. Many have had difficult childhoods, or grown up in workless households, with no one to turn to for advice about how to apply for a job or do well in an interview.
They may look up to successful people they see in the media, but without the right support, they feel that their own dreams are out of reach.
At The Prince's Trust, however, we are determined to prove them wrong. As well as offering practical support to disadvantaged young people, we have built a network of volunteers who dedicate their time to helping young people get their lives on track.
Many of our volunteers act as mentors to young people in their areas, offering vital support and guidance to young people taking their first steps on the career ladder. We also have an army of business mentors who support young people on our Enterprise programme, which has helped 80,000 young entrepreneurs over the last 30 years.
When I first joined The Prince's Trust, I was especially keen to engage more female supporters to act as role models to the young women we support.
In 2006, I set up a 'Women's Leadership Group' - a fundraising initiative which unites successful women to support and inspire young people.
Seven years later, the group is made up of almost 50 influential women from sectors including finance, recruitment, media and retail, as well as leading entrepreneurs such as Liz Earle MBE and Chrissie Rucker MBE, Founder of The White Company - who have contributed their own resources and worked together to raise more than £3.7million in support of our work.
Women like Chrissie Rucker MBE and Liz Earle MBE are fantastic role models to young women not only because they have trail-blazed their way to the top but because they are also willing to share their time and expertise to help the next generation do the same.
We are fortunate in Britain to have so many successful women who act as fantastic role models to others. I feel honoured to be included alongside some of them in the shortlist for this year's First Women Awards, sponsored by Lloyds TSB.
I never fail to be amazed by the difference that a great role model can make to a young person's life. I recently met a young woman called Afsana Benozir who suffered abuse as a child and became homeless as a teenager. By the age of 16 she had given up on her ambitions, but with help from The Prince's Trust she learned to believe in herself again and is now training to become a doctor.
At a recent fundraising event for our Women's Leadership Group, Afsana described a good role model as someone who helps others to "dream more, learn more and become more." I believe passionately that all young people need and deserve someone like this in their lives.
The Prince's Trust is currently celebrating 30 years of its Enterprise programme, supported by RBS. To find out more visit www.princes-trust.org.uk/30Enterprise.
Martina Milburn is shortlisted for the 2013 First Women Awards.
The awards ceremony will take place on Wednesday 12 June and is hosted by Real Business in association with Lloyds Banking Group.