BACKGROUND: Favourable Conservation status (FCS) is the overarching goal of the Habitats and Birds Directives, in which it is described as the situation in which a habitat or species is thriving throughout its natural range and is expected to continue to thrive. However, despite being introduced over thirty years ago, FCS has not been widely adopted as a conservation assessment framework. This systematic map aims to collate and characterise evidence to understand 1) how the term FCS is used in the literature, and 2) the context of its applications in policy and practice. Specifically, we ask the question: how is FCS defined and how has it been applied in policy and practice? This review will contribute to the field by providing the first systematic evidence synthesis on FCS, both as a concept and as a practical application, and will review the broader applicability of FCS beyond Member State reporting obligations. METHODS: A systematic search of the literature will be conducted to collate and categorise evidence on the definitions and applications of FCS and barriers to its implementation. The literature will be screened in two stages to assess relevance, firstly by titles and abstracts and secondly by the full-texts. Studies will be assessed against eligibility criteria pertaining to the components of the question. Coded data will be extracted from the relevant studies and used in a narrative synthesis to summarise the evidence in a discussion, complemented by descriptive statistics and visual aids.