Professor Peter Curwen was until September 2002 Professor of Business Economics at Sheffield Hallam University, in the UK. He is now retired from his full time role but remains Visiting Professor of Telecommunications Strategy at Strathclyde University where he began to research and publish jointly with his co-author. He has spent the past decade building up a unique set of databases on mobile telecommunications technology containing information otherwise unavailable in the public domain. Dr Jason Whalley is Reader in Management Science at Strathclyde University. Since roughly 2000, he has concentrated his research on mobile telecommunications, and in particular upon the structure of the industry and the strategic behaviour of operators. Both authors have published extensively.