The British Army calls it "fighting in built-up areas", or "FIBUA"; the US Army calls it "military operations on urban terrain", or "MOUT". It has other names, too, such as "conventional warfare in an urban environment", and most straightforwardly of all it is sometimes called "street fighting". Whatever the terminology, urban combat is becoming increasingly relevant in modern warfare, with vast sums being invested by NATO armies in building relevant training facilities. The British Army alone has one major facility in West Berlin, a second more recently completed on Salisbury Plain and a third planned at Sennelager in Germany. The urbanization of Western Europe is now such that in any future war it would be difficult not to fight in urban areas, and urban combat has consequently become a technique of major military significance. This book discusses its contemporary theory and practice.