In my thesis I investigate the vegetation and phytodiversity of Baltic Sea saline and brackish grasslands, focussing on methodological, ecological and nature conservation aspects. My co-authors and I conduct analyses based on my own data and compiled historical and current data, which we propose to transform to make them applicable for further analyses (Pätsch et al. accepted a). We jointly describe the Baltic Sea coastal grasslands along the entire coastline in relation to their ecology, littoral placement, geographic patterns, phytogeography and assignment to North-west European salt grasslands. We further review their conservation aspects (Pätsch et al. accepted b). Based on analyses of characteristic species of low-growing coastal grasslands in relation to Elytrigia repens, we elaborate a proposal for assessing the quality of coastal grassland vegetation (Pätsch et al. 2019).