The row over the sub letting of First Minister Henry McLeish's constituency office has thrown the issue of MPs' expenses into the spotlight.

In addition to a parliamentary salary of �49,822 there are a number of allowances which can be claimed by those serving at Westminster.

Office Costs Allowance

MPs are given an allowance from the public purse to pay for office costs incurred in the course of performing their parliamentary duties.

They can claim up to �52,760 per year for the cost of secretarial assistance, general office equipment and the employment of research assistants.

House of Commons figures show that this has risen massively since 1969, when MPs could claim up to �500.

However, if an MP sub lets part of his or her office, the rent paid by those tenants should be offset against this allowance.

MPs are also entitled to free stationery and postal services from the parliament, along with free inland telephone calls.

Travel costs

Since 1984 there has been an entitlement to a limited amount of free travel for MPs' staff, who can claim for nine journeys between their constituency and Westminster each year.

MPs themselves receive free travel to and from the House of Commons and while on parliamentary business in the UK, or are able to claim a mileage allowance.

MPs are also able to claim a bicycle allowance of 6.9p per mile for journeys they undertake while on parliamentary duty.

The spouse and children of an MP can also make up to 15 journeys each year from their constituency for free.

Supplementary London Allowance

There is also an additional cost allowance of up to �13,628 available to backbenchers who live outwith London.

The money is available to cover the cost of overnight stays away from the MP's home.

Winding Up Allowance

Up to a third of the annual office costs allowance is available to cover the parliamentary work carried out by an MP on behalf of a colleague who has died, retired or been defeated.

MPs whose time at Westminster comes to an end at a general election are also entitled to a resettlement grant of between 50 and 100% of their salary.

This payment, which is designed to help adjust to "non-parliamentary life", is based on age and length of service.