This study was conducted within the scope of the Master's dissertation in Clinical Psychology. Although global sustainability and sustainable development are issues that are increasingly being addressed, there is still a need to better understand the psychological aspects involved in environmental actions. Thus, the validation of the Environmental Action Scale (EAA) for the Portuguese population aims to meet the need for assessment instruments in this area.The study is divided into two sub-studies: validating the EAA for the Portuguese population and assessing the concurrent validity between personality and environmental action using the ICR-T.