The new architecture of the buildings, the legal reforms, especially criminal law, the propaganda had Pax and Securitas as essential conditions and prerequisites in particular in Rome, its ports and more generally in the whole of Italy and Latium. The aim of the emperor was to ensure the security of places and the protection of the inhabitants of Rome and himself, the Securitas Augusti et populi Romani, as an internal precondition for the Pax Romana. It was the solution to both the recurrent problems connected with security and the launch of an experimental process. It might seem that 'public order' and 'security' are two different ways of defining the same substance. It is not so: public order was not always the centrepiece of Augustus' policy – and of his successors' who more systematically adopted his same action – which was defined from a more comprehensive perspective, attentive to the daily life and problems of the city.