Surveillance and monitoring of ancient structures: Recent developments.

The general criteria for the design of a monitoring system to assess the static behaviour of a structure are presented as well as the different types of instruments which are used. Special emphasis is devoted to automatic monitoring, but manual reading techniques are also examined. Some important examples are then presented which illustrate the use of monitoring for the analysis of long-term behaviour of a structure (SI. Mark's Basilica in Venice) far the control of restoration works (Metropolitan Cathedral in Mexico City) and for the surveillance of the safety conditios of an important structure affected by a catastrofic event (Chapel of the Holy "Sindone" in Turin).