The original CERN convention, which was drafted nearly 60 years ago, foresaw that the organization should have a role as co-ordinator for European particle physics, as well as operating international accelerator laboratories. Today, this role is more appropriate than ever: the long lead times usually required to prepare and construct facilities and experiments for modern high-energy physics, together with the increased costs for these activities, underlie the need for a general European strategy in the field. So it was natural for CERN Council to initiate the creation of a European Strategy for Particle Physics in June 2005 and to establish dedicated groups for reviewing the scientific status and producing a proposal. They consulted widely with the community, funding agencies and policy makers in preparing the strategy document, which was adopted by Council in July 2006 during a dedicated session in Lisbon.