In this paper, we are interested in assessing the different environmental security concepts, policies, and actions of actors involved in the Common Security and Defence Policy (CSDP). Through exploratory qualitative research, we interviewed key stakeholders who formulate both the climate security discourse and its policy outcomes. Aiming at finding the different perceptions and practices among various actors, we conducted 27 qualitative interviews with practitioners from 17 different institutions, such as EU bodies and agencies, think tanks, and ministries of defense (MoDs). This article discusses the divergence between announced environmental and climate security strategies and policies related to their actual results. Notably, the findings indicate that the effectiveness of the political directives compared with the practices and the developed capabilities around the environment–security nexus are dependent on individual initiatives and efforts that a developing community of practitioners is attempting to carry out. Our study indicates that tailored environmental security policies and actions are needed to motivate both practitioners and policymakers to develop downstream methods and programs that are suited to resolving security-related challenges associated with environmental issues and especially climate change.