The EU Strategy for the Baltic Sea Region and its Action Plan requires cooperative actions on the transposition of EU Directives and defines the MSFD as the strategic, horizontal action. Implementation of MSFD in Member States is in the phase of drafting initial assessments, determination of good environmental status (GES), establishment of targets and indicators, and establishment and implementation of relevant monitoring programs. According to Article 6 of the MSFD Member States should cooperate to ensure the coordinated development of marine strategies in the same marine region. Here the role of regional sea conventions (Helsinki Convention in the Baltic Sea area) is outlined. However, close cooperation of institutions involved in the MSFD implementation in a sub-regional scale (in the central Baltic region) will secure rapid enough and profound results/outputs in the relatively diverse Baltic Sea and, in turn, contributes to the Baltic wide MSFD implementation activities. Thus, this project is directly linked to the parallel work in HELCOM and is the national and sub-regional contribution rather than duplication. We defined the main issues, where joint actions and harmonization of MSFD implementation products are needed, as it follows: harmonization of initial assessments between countries sharing same sub-regions, in particular, sharing of information regarding assessment of pressures; joint attempts to fill in gaps regarding GES descriptors not well enough addressed so far under different directives/assessment procedures; joint development of monitoring programs with possible sharing of responsibilities and infrastructures; joint economic and social analysis of the use of the sea and the cost of degradation of marine environment. According to these main issues five inter-related work packages were planned: WP1- Project management and coordination with main focus to guarantee high quality administration, communication and publicity. In WP2 a detailed analysis of initial assessments for coherence and gaps is conducted. Report on gaps in data and knowledge will provide input to other work packages where advancing of knowledge base and capacity building to support assessment of GES (WP3) and development of a joint monitoring and assessment scheme (WP4) is planned. A central WP – WP3 will concentrate on analyses of methodologies for the following descriptors: non-indigenous species, food webs, marine litter and underwater noise. In WP4 the outputs form WP2 and WP3 will be taken into account when developing a joint, scientifically sound and cost-effective monitoring and assessment scheme. The use of autonomous platforms for monitoring, operational modelling results for assessment and methodological aspects of aggregation of indicators will be addressed. WP5, which is linked to coherence analysis of initial assessments in WP2, will cover a number of economic and social analysis issues and capacity building in this field Achievements: The main aim of the project was to support coherent and coordinated implementation of the Marine Strategy Framework Directive in the central and north-eastern sub-regions of the Baltic Sea. The GES-REG project has improved marine environmental management in the region via dissemination efforts towards the the environmental authorities, institutions responsible for marine monitoring and assessment, HELCOM and the wider public. The project produced publications and organized seminars and meetings for the environmental officials.