Our monitoring of Parliamentary Questions spat this one up today. Self-explanatory really.
Mr Jenkin: To ask the Secretary of State for Foreign and Commonwealth Affairs with reference to the letter from the Minister for Europe of 11 November 2010, on the European Union Bill, for what reasons his Department believes that the present terms of UK membership of the EU are in the national interest. 
Mr Lidington: There are many things about the EU we would like to change. However, membership of the EU gives UK business full access to the world’s most important trading zone, comprising 500 million consumers without the barriers of customs or tariffs. This is of great importance to the UK’s prosperity. 10% (3.5 million) of UK jobs are reliant on exports to EU member states, the beneficial effect of EU trade on UK households is estimated at between £1,100 and £3,300 per year, UK exports to member states are worth more than £200 billion, and EU Foreign Direct Investment (FDI) comprises 49% of overall FDI to the UK. Under the present terms of membership the UK plays a strong and active role in influencing and shaping developments within the EU, allowing us to further goals essential to the national interest, such as strengthening and expanding the single market, delivering growth, and promoting a resource efficient, low carbon EU economy. The European economic area (EEA) and European Free Trade Association (EFTA) members, in contrast, have to contribute to the EU budget without being able to negotiate the detail and content of EU legislation, and without receiving benefits such as the exemption from customs requirements and costs.
In addition, EU membership gives the UK better leverage and negotiating power on the global stage, allowing us to better achieve our international objectives on issues such as freer international trade, conflict prevention, stabilisation, climate change, human rights and development. There are also wide-ranging benefits for UK individuals, such as the right to study and work within the EU, and to receive free or reduced cost health care on temporary visits within EU member states.