The sea knows no borders – the decisions about economic development and resource use in one Baltic Sea country can influence all countries bordering this already impacted marine area. Increasing maritime activities in the Gulf of Finland area and the uncoordinated use of coastal and marine areas have become problematic for the marine environment and maritime-based economies. The current EU directives set forth the requirement for unified and transboundary actions in order to address common challenges in these marine environmental issues. Similarly, the trilateral cooperation between Russia, Estonia and Finland has clearly indicated a need for a common management approach in the Gulf of Finland region. A fundamental component for the design of efficient policies and real management actions is knowledge about impacts of pressures on the spatial distribution of biodiversity and ecosystem functions. Separate and interactive effects of various human-induced pressures on the environment is far from being well understood, resulting in ineffective management measures. In the ADRIENNE project we assess how alternative human uses either alone or combined with other pressures may affect diversity, ecosystem functioning and services in the highly utilized and sensitive transboundary waterbody of the Gulf of Finland. In order to achieve this goal, we will combine novel spatial modelling products of species, habitats and fishery-related ecosystem services with expert-based assessment of synergistic effects of human uses on the biota and vice versa. This knowledge is summarized in a GIS portal with a capability of assessing interactive responses of various human-induced stressors on the Gulf of Finland ecosystem under different human-induced nutrient loading and climate change scenarios. The established Assessment Portal is unique as it is built on harmonized methodologies, big data with high scientific quality and novel machine learning modelling framework. From the user side, however, it is simple and highly self-intuitive to use. The used methodologies involve analyses of the status and trends of different sectors, focusing on the important economic drivers and pressures in the Gulf of Finland area. Here we consider all sectors related to marine exploitation with an emphasis on fishery, eutrophication, nuclear power plant exploitation, different types of disturbance of the seabed, and alien species. In this project, we develop novel approaches with a capability of addressing the impacts and risks of climate change in interaction with other human mediated stressors for species, habitats and associated ecosystem services in the Gulf of Finland ecosystem. As such, the project helps to find new ways to mitigate risks of intensified human uses and climate change in the fragile and valuable ecosystem of the Gulf of Finland. Moreover, by ensuring an effective transboundary engagement of key stakeholders through all our activities, the project fosters multidisciplinary co-operation and communication in Russia, Estonia and Finland concerning issues related to the protection of marine nature and human activities in the Gulf of Finland region. As key outputs, the ADRIENNE project provides harmonized map layers of key environmental variables and sea uses as well as common algorithms on how multiple human uses affect the biota and likewise how disturbed ecosystems are linked to the losses of human uses. The environmental value layers include high resolution maps of benthic biodiversity, species and habitats, spawning and nursery areas of commercially important fish species and associated ecosystem service values. The pressure layers focus on eutrophication via point and diffuse sources, fishing, shipping, construction and energy sectors and their synergistic effect on the biotic layers above. The current project also results in the GIS Assessment Portal for maritime spatial planners and resource managers with a capability of assessing interactive responses of sector-specific human-induced stressors on the Gulf of Finland ecosystem under different nutrient load management and climate change scenarios. The Assessment Portal also serves as an efficient dissemination of all novel information of joint natural assets to environmental managers, planners and a wider public. Protecting the environment and sustainably using nature values are the core responsibilities for spatial development policy, development strategy and the development of spatial plans. Ultimately, the project will target limitations of current maritime spatial planning practice and resource management as well as address common transboundary challenges in marine environment issues. The improved biodiversity of joint natural assets will be achieved by smart planning and increasing awareness of environmental protection.