It has also set itself a benchmark for judging whether it gives value to shareholders, by promising over the long term to beat the total return, including dividends, of the FT Actuaries all- share index and a specially chosen index of financial services competitors.
An unusually detailed corporate mission statement that has taken two years to prepare defines the bank's principal business as the 'manufacture and distribution of personal financial services in the UK'.
Against a background of embarrassing losses from a foray into estate agency in the late 1980s, the statement assures management and staff that Abbey plans to stick to its last and not suddenly leap out in other directions.
It says: 'We will broaden the base of our company by developing related businesses in the UK and Europe only where we can obtain the expertise and resources to attract good quality financial customers, and achieve significant and sustainable competitive advantage.' Briefing documents given to staff with the unpublished statement say: 'Don't worry - we are not going to be rushed into areas we know nothing about. Our purpose is to create shareholder value, not destroy it.'
The statement is also cautious about expansion in Europe, where the bank's early investments in France ran into problems. It says only that 'in the long run' selected Continental European countries will contribute to the bank's success. But the statement does underline the importance of the bank's successful treasury department to future performance.
Abbey's main markets, the statement says, are secured and unsecured lending, short- and long-term savings, insurance protection and personal banking.
The document says: 'Our underlying purpose is to achieve above- average growth in shareholder value over the long term. This can only be accomplished if we meet the needs of our customers, our staff and all of the other stakeholders in our business.'
The bank says it intends to generate above-average growth in the present value of future cash flow. As well as the FT Actuaries benchmark, it will measure its performance against building societies and clearing banks, probably picking 10 companies for comparison.
Abbey has easily beaten the all- share index since its flotation in 1989, with its share price trebling.
Abbey's previous mission statement was one sentence long, defining the bank's business as meeting personal financial needs. But John Fry, a director, said it was a factor in the bank's decision not to go into commercial lending in 1990, a period that produced heavy losses for some banks.
The new statement spells out objectives in detail because it is to be used as a management tool at group and subsidiary level, Mr Fry said.