The UK has been collaborating with international, primarily European partners in the design, development and production of advanced combat aircraft for over sisty years. Driven by a combination of rising costs and limited domestic markets, collaboration has also been a highly political act involving a combination of national, industrial and technological interests. Over the years, the form of collaboration has evolved, in some cases leading to the creation of transnational companies. The UK has been a pioneer of globalisation in the defence industry, establishing a strong presence inside the US defence market and has become a significant partner with American companies in key military aerospace programmes. This has contributed to divisions within the European military aerospace industry which are likely to continue into the next generation of combat aircraft.