As Europe's leaders gathered in Rome to sign the new EU constitution seven politicians and business leaders gave their thoughts on what it could mean for Britain.
British consumers, British business and the British economy have all benefited from membership of the EU.
The Labour peer has advised Tony Blair on rural issues and is an EU-enthusiast
The public has enjoyed more choice and better value arising out of a more competitive market - one only has to look at the range and quality of cars available from across the EU.
Britain's long term relative economic decline has been arrested, and many economists would argue that membership of the EU has been a critical factor, as the protectionism of imperial and Commonwealth preference gave way to the fiercely competitive EU market.
However UK productivity still remains far short of that in Germany, France and most other western EU economies.
Britain has also been the main beneficiary in attracting investors from North America and Asia, keen to exploit the opportunities of the EU market, though it looks as if this benefit is now being eroded as investors are moving to the eurozone area because of our ambivalence about the single currency.
Businesses thrive in a stable political environment. The EU has delivered unprecedented peace to western Europe, and this stability seems likely to spread to the turbulent east as the new EU members recognise that this is one of the greatest attractions of participation.
The enlarged EU will offer further benefits to British business and consumers.
Sensible business people recognise, however, that institutional changes are necessary if the enlarged EU - which we all welcome - is to be manageable and accountable.
It is much harder to achieve agreement between 25 as opposed to 15 members and many of the administrative arrangements were designed for a six country EEC.
The constitution addresses these issues in many ways:
Streamlining the decision making process through a wider use of Qualified Majority Voting, whilst still requiring unanimity on the crucial areas of taxation, foreign and security policy
Simplifying the complex structure of EU treaties which have been agreed over many years
Making the Commission more accountable to the European and national parliaments in the policy making and delivery process
Improving the day to day effectiveness of the EU by the creation of a European Council president and a European foreign minister
Most of these changes are merely intended to improve the delivery of existing policies, although it makes sense to strengthen the EU's responsibilities for immigration and the environment, where European cooperation is in our best national interest.
But the constitution is much less significant in its impact on national sovereignty than most other treaties, notably the Single European Act, which Mrs Thatcher signed.
She rightly conceded primacy of the EU over national judiciaries with regard to various disputes related to the workings of the single market.
But there are others who argue for a radical renegotiation of existing treaty obligations including, for example, fisheries.
Withdrawal an option
This position seems somewhat unrealistic, because a renegotiation would require the agreement of all the other 24 members, and this would be highly unlikely because of the precedent it would set.
Besides even if we did withdraw from the Fishery Agreement, where would we sell all the British fish which we now export to France and Spain?
For sceptics who have understood the fallacy of this position, the treaty offers another option - that of total withdrawal from the EU.
The unravelling of 30 years of economic and political integration would be a perilous business.
Such a process would be slow, costly and create enormous uncertainty in currency and trading markets.
Stability over uncertainty?
Business would in such uncertainty find profitability and investment at risk.
And even if this hazardous path was embarked upon where would it lead - to the absurd position that Norway finds itself in, signing up to all the rules of the single market without being a voting member.
The other option of joining the North American Free Trade Area is even more farfetched.
Britain must sign up to the EU constitution because it will strengthen rather than weaken arrangements to make the European Single Market more effective.
Stability must prevail over uncertainty.
The constitution should be welcomed by British business for all these reasons.