“How safe are our bridges?”Although a lot of research on structural safety has been performed during the last decades, answering this question for existing structures is still a challenging problem engineers are increasingly confronted with. This is mainly because a proper framework for assessing the safety of ageing or even deteriorated structures that can properly take into account the results from inspections and monitoring is still missing. Nevertheless, it is a very important and relevant issue as all of us make daily use of transportation infrastructure. “How can we optimize investments in inspection of bridge infrastructures over their lifetime?”As the resources for management of the bridge patrimony are limited, it is important to ensure that they are used in an optimal way. Hence, this research proposal will focus on (1) developing a framework that allows assessing existing concrete bridges by means of a Bayesian pre-posterior decision making tool that takes into account time-dependent behaviour and monitoring information and (2) determining and optimizing the value of monitoring over the lifetime of the structure. This enables an optimal allocation of the limited resources available for asset management