Paul Coby here proposes a new system for the recording and mapping of Roman forts and fortifications that integrates all the data, including size, dating and identification of occupying units. Application of these methods allows analysis that brings new insights into the placement of these forts, the units garrisoning them and the strategy of conquest and defence they underpinned. This is a new and original contribution to the long-running debate over whether the Roman Empire had a coherent grand strategy or merely reacted piecemeal to emerging needs. Although the author focusses on several major campaigns in Britain as case studies, the author stresses that his method's are also applicable to elsewhere in the Empire. Lavishly illustrated with colour maps, the book is also supported by a website and blogs, encouraging further investigation and discussion.