SARETH Nainby-Luxmoore has never been diagnosed as dyslexic. But she is fairly sure she has had the trait from being very young.

And it is one reason she is keen to give numeracy help to young men at a County Durham young offenders institution.

This charity work has absorbed her. And it will feature strongly on her agenda when she takes over as the county's High Sheriff in 2006.

It may be more than a year away, but Mrs Nainby-Luxmoore is already preparing the ground for her year in office.

"You don't want to spend the first six months getting things organised," she said. "You have to hit the ground running."

It was the energetic charity work of both herself and her husband which sparked her nomination for the role.

Along with Jonathan Nainby-Luxmoore - a GP in their home town of Middleton-in-Teesdale - she works tirelessly for good causes such as the hugely successful Durham Shopping Extravaganza, which brings in about £20,000 a year for charity.

The mother of three boys aged seven to 14, Mrs Nainby-Luxmoore was born in Scotland and as a youngster travelled with her soldier father around the world.

She worked in London for 15 years, starting off as a clerk in a stockbroker's office and working her way up to be a pension fund investment manager.

Now 45, she has lived in Teesdale for just over 13 years.

"I have the privilege of being a housewife," she says.

But having said that, she is currently studying for a teaching certificate at Darlington College of Technology, and she is also a member of Middleton in Teesdale Parish Council.

"I have no degree," she said, "as I went straight to work in the City from school. I had a place at uni but didn't take it up. Teaching has always appealed to me. I think it's in any human being to want to teach a little bit."

That part of her character got a boost when she was standing in Witham Hall in Barnard Castle and saw an advert for volunteer support tutors at Deerbolt YOI.

The teaching course was available through the Government Link-up Programme, which is directed at improving basic skills.

"My eldest son, Oliver, has dyslexia and we have the same brain pattern," she says. "At school I was told I was stupid, dyslexia not being recognised then.

"When Ollie went to school he learned how he could get away with doing nothing all day and I was picking up a flatter and flatter child. He isolated himself because he found certain subjects hard.

"This was one reason I wanted to get involved with the lads at Deerbolt."

Mrs Nainby-Luxmoore says she is no longer shocked at the inmates' lack of knowledge.

"It can be very basic. One lad did not know how to use the 'times' button on a calculator. But I have seen young men completely change. They find they can do things after all and they blossom."

Of her own condition she says: "I am sure I am dyslexic, but it has never been diagnosed.

"I like to think it has not held me back, although it may have eroded my confidence at times."

She is now working with a group of inmates on budgeting and money management.

"I find it ironic that I used to invest millions for pension funds," she said. "But the lads are hot on market forces and understand what it's all about. I have never had a problem with numbers. But I know what it's like to either come up against a brick wall or have the shutters come down on you."

Her course ends in June. But she won't be looking for work until after her stint as High Sheriff.

"The work at Deerbolt is incredibly rewarding," she said. "I have always wanted to help people with numeracy. If you can't even fill in a form, then you are almost left with no option but to be illegal and thieve."

Complementing her activities, Dr Nainby-Luxmoore is a trustee of St Teresa's Hospice and Upper Teesdale Agricultural Support Services, which was recently visited by Prince Charles

"We don't come from this part of the world, but we have adopted it and got involved," she said.

Being High Sheriff is voluntary and unpaid. A panel nominates people to go on the list for the position and the Lord Lieutenant is consulted about the choice.

Largely representational, the post involves looking after judges who are travelling to courts, and to attend court if necessary.

It also aims to build on the morale of the community, liaise between different organisations and support charities.

"If we can encourage more money to go into prisons for learning that would be good," said Mrs Nainby-Luxmoore.

She also wants to bring to the area a sewing charity based in the south which encourages prisoners to create tapestries and such. It aims to harness prisoners' time and skills - to sell to up-market designers.

"Anything I can introduce along on those lines I will," she said. "I am looking forward to it. I am marginally apprehensive but determined to do my best for County Durham.

"I believe Middleton in Teesdale has adopted us. If I can give something back to the community through my role as High Sheriff it will be a great pleasure to do so."

That just leaves the question of ceremonial dress.

The office of High Sheriff has not been occupied by many women in its 1,000-year history. Ladies can choose the attire they want - including the sort of breeches worn by male incumbents.

Mrs Nainby-Luxmoore has gone for a black velvet dress and coat, being made for her by Caroline Soullier of the Selfishly Mine bridal design business at Ovington.

"I just hope it suits me," said Mrs Nainby-Luxmoore