Description: This report reviews the current situation as regards to the Marine Strategy Framework Directive (MSFD) Descriptor 1 (Biodiversity) for pelagic habitats and serves as a basis for a workshop with Member States experts and scientists that will be held on March 9-10 2021. Recommendations are in the concluding section. Pelagic habitats cover the 71% of Earth’s surface and play an essential role in regulating temperature on land, producing oxygen and food. They are also a management challenge where the alterations of their physical, chemical and biological characteristics negatively impact their ecosystem functioning and services (e.g. provisioning services). To address these challenges, the MSFD has required the assessment of pelagic habitats against environmental targets to reach Good Environmental Status (GES). A key step in the pelagic habitat assessment is a thorough understanding of its physical, chemical and biological processes and the drivers that underlie the spatiotemporal variability in its ecologically relevant ecosystem components. However, pelagic assessments to date have not sufficiently addressed the functional and structural characteristics of pelagic habitats processes, which is limiting our ability to inform on their environmental status and to disentangle the anthropogenic drivers. This report evaluates previously published work on pelagic habitats assessments considering the actions and targets to meet the MSFD requirements. To do this, the report (i) summarises the main drivers of variation in pelagic habitat characterization; (ii) reviews the common empirical approaches used to assess pelagic habitats, the advantages, and challenges; and finally (iii) exposes a set of recommendations for characterising pelagic habitats in EU waters. Since the pelagic habitats are made of a highly dynamic fluid, appropriate spatiotemporal scales regarding data and methods must be considered to assess their GES. This applies in particular to the selected indicators to propose the effective and quantifiable GES targets that need to be reached.