Commissioned by UK Office of Science and Innovation, the report looks at the trend of international scientific collaboration between the United Kingdom and its leading partners. It uses bibliometric data (co-authorship and citations of scientific articles) to capture international scientific collaboration in seven broad research fields, focusing on Australia, Canada, China, France, Germany, India, Japan, UK and the US. The data deals with two time-periods, 1996–2000 and 2001–2005 and the report finds that publication of co-authored articles on scientific collaboration has increased considerably faster than the overall increase in research across the two time-periods. It also finds that countries vary in their ability to collaborate or to benefit from it. The results may have important implications for putting international scientific collaborative arrangements in place.