||Here we present such a framework based on the DPSIR (Driving forces-Pressures-State-Impact-Response) causal framework. DPSIR has been used to assess environmental impact of human activities by the European Environment Agency (EEA 1999, EEA 2014), United Nation Environment Programme (UNEP 1997, UNEP 2012), and – more recently – to environmental impact of visitors in PAs (Navarro et al. 2012, Salerno 2013). However, the focus of DPSIR is on the state of the environment and impact on humans, while other important factors such as impact on the visitor satisfaction, and park services, are not included in the analysis. Our framework treats tourist activities as the driving forces, and connects the causal chain of Activities – Pressures – State – Impact – Response and Services (APSIRS, Figure). Unlike prior frameworks, we interpret the state as the state of all entities in the NPA, not just the environment. The entities are composed of four types of objects: people, cultural heritage, NPA services, and the environment. The state of the objects is quantified by indicators compatible with EU regulations and conducive to valuation of ecosystem services (ES), and can be evaluated subjectively (e.g. through opinion polls) or objectively (e.g. through sensors).