Glass used to work for the Civil Service but left to start a family. The author decided to foster a child after trying unsuccessfully for a baby with then husband John; she had seen an advert in her local paper seeking a foster home for a girl named Mary and applied.

Glass and her husband were assessed as foster carers - a process that now takes about a year - but they discovered Mary had been found another foster home.

Instead, they fostered a 15-year-old boy called Jack, who had been removed from his home after his stepfather broke his nose. The couple looked after Jack while his father, who was at the time living in a bedsit, found a suitable flat.

Three months into his stay, Cathy discovered she was pregnant with her son Adrian, now in his 20s. Despite having a baby, Glass continued to foster, taking on Dawn, a shy and polite 13-year-old who Cathy came to treat as a daughter.

Dawn proved much harder to parent due to her background and in the end had to move to a residential home with professional therapeutic help. Over the last 23 years, Glass has fostered over 50 children aged three to 16, including several like Dawn who, as a result of past experience, had behavioural issues.

Because of the challenging behaviour and special needs of many of these children Glass usually only takes one child at a time. Some have stayed for a few nights or weeks while others for a year or two.

She went on to have another child of her own, Paula, now in her late teens, and also adopted Lucy, now in her early 20s, following a long-term foster placement. In an interview with the Daily Mail, written by Kate Hilpern and published in February 2009, Glass listed some of the abusive backgrounds the children she has cared for have come from.

At the extreme end, these include being forced into prostitution and having to work in a sweatshop. Many of the foster children had been physically or sexually abused and a large number had come into care as a result of severe neglect.

As a foster carer, Glass receives ongoing foster training and because of her experience she is asked to take on some of the more challenging children in the system.

In 2010, Glass released Happy Kids: The secret to raising well-behaved, contented children - described by publisher HarperCollins as a "fresh and practical guide" to successfully managing children's behaviour.

It introduces the reader to Glass's own 3 Rs technique: Request, Repeat, Reassure.

The 3 Rs technique is noted as a successful strategy for managing children's behaviour based on the three key principals of request, repeat and reassure .

Cathy has always had an interest in writing, combining fostering with occasional freelance journalism and commercial writing, usually when a particular issue stirs her passion. Before the success of Damaged she had written on health and social issues for The Guardian and the Evening Standard.

She is also a published fiction writer, with poems and short stories in a number of commercial magazines.

Glass's first book, Damaged was released in 2007. It focuses on the relationship between Glass and Jodie, an abused child. Jodie had been at the centre of a paedophile ring before being brought into foster care. A year later, in March 2008, Glass followed up with Hidden.

Glass's third book, Cut, released in February 2009, told the story of Dawn, the second child Glass fostered.

The Saddest Girl in the World was released in October 2009, and like the three previous books, told the real life story of one of Glass's foster children. The book centres on Donna, a 10-year-old who was seriously, physically and mentally abused by her alcoholic mother.

Glass has described writing as a sort of therapy: “certainly telling the children's stories helped me to come to terms with what the children had been through.”

Glass's next book was a departure from the inspirational genre, being a parenting manual - Happy Kids, published in 2010.

In April 2010, she released her first novel, The Girl in the Mirror. Based on a true story, the novel centres on Mandy, a woman in her 20s who sets out to rediscover her past after buried childhood memories start to surface.

Her latest memoir, I Miss Mummy, will be published in July 2010.

Glass has had great success as an author, with Damaged being a number 1 Sunday Times bestseller, both in hardback and paperback. To date her books have sold 0.7 million copies. Cathy's books are also available in large print and have been translated into Danish, Norwegian, Polish, Portuguese, Russian and Swedish.

Though her works deal with harrowing subjects — in a 2007 article on Misery Literature Daily Telegraph writer Ed West cited Glass's Damaged as being among “the most disturbing recent examples of the genre.” - other reviews have praised Glass for her moving narratives and sensitivity, promotion of fostering and her underlying message of hope.

Reviews of her books have appeared in British women's magazines OK!, First, Heat, in national newspapers the Daily Mirror, The Sun, and on website adoption-net.co.uk.