The global scientific landscape is changing rapidly. New scientific powers are emerging, and international collaboration is growing dramatically. In the first part of this talk Professor Sir Chris Llewellyn Smith (Director of Energy Research, Oxford University and President of SESAME Council) reviews these changes as a prelude to discussing attempts to harness global science to address global problems such as climate change, the spread of diseases and the loss of biodiversity. In the second half of the talk he reviews the status of SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) as an example of a project with the dual aims of building scientific capacity and building bridges between people in diverse countries though scientific collaboration. SESAME, which is modelled on CERN (Smith was also the Director General of CERN from 1994 to 1998 when the LHC was approved and commissioned), is a third generation light source under contruction in Jordan and the Middle East's first major international research centre.