Guiding documents under the 'PEC' acronym are commonly used in environmental education centres (EECs) in Spain. They are written documents that are seen as necessary tools to safeguard quality. In this study, we analyse the guiding documents of twenty-three EECs in the province of Girona (Catalonia, Spain) in order to understand their contents and detect strengths and weaknesses. The instrument used for document analysis is a rubric created for this purpose from the literature review. It includes four main sections: identity features, context analysis, formulation of goals and a plan of action. Each of these sections has associated items that have been used to analyse the guiding documents mentioned. The results show a great lack of information regarding evaluational aspects. They also show difficulties in defining the concepts of environmental education or education for sustainability and relating sustainability to the milieu of EECs.