Here we go.... found what I was looking for. using quotes from wikipedia (easier then retyping):
The United Kingdom has an opt-out from eurozone membership under the Maastricht treaty and is not obliged to join the euro. While the government is in favour of membership provided the economic conditions are right (requiring that "five economic tests" be met), the question has never been put to referendum.[24] The United Kingdom was forced to withdraw the pound sterling from the ERM (the precursor to ERM II) on Black Wednesday (16 September 1992) due a mismatch between its benchmark currency parity and its economic performance, and the pound is not part of ERM II.
Where-in these five tests include:
1. Are business cycles and economic structures compatible so that we and others could live comfortably with euro interest rates on a permanent basis?
2. If problems emerge is there sufficient flexibility to deal with them?
3. Would joining EMU create better conditions for firms making long-term decisions to invest in Britain?
4. What impact would entry into EMU have on the competitive position of the UK's financial services industry, particularly the City's wholesale markets?
5. In summary, will joining EMU promote higher growth, stability and a lasting increase in jobs?
In 2001 and 2003, the government assessed these questions and found that joining the EMU would only be beneficial if convergence and flexibility were sufficient. So, that is why you guys still use the Pound though the Euro is accepted in some places throughout the country.
Ox
