At the ﬁrst and second Workshop on "Charophytes in the Baltic Sea" a ﬁrst attempt was made to get an overview on the distribution and status of Charophytes along the Baltic coastline. These workshops, assisted and ﬁnanced by the unit "Marine and Coastal Nature Conservation" of the Federal Agency for Nature Conservation (BfN) on the Isle of Vilm, united the expertise of 20 specialists of all Baltic countries. Therefore for the ﬁrst time not only a survey about the distribution could be gathered, but also trends in population dynamics could be shown and potential thread factors were identiﬁed. As a result of these workshops, a catalogue of tasks was agreed on which will be tackled by a newly founded working group of the "Baltic Marine Biologists" (BMB). This catalogue includes the compilation of data needed for a "Red List" and the preparation of a common determination key for Charophytes of the Baltic ecoregion. In this issue the ﬁrst results about the Charophytes in the Baltic Sea are presented.