With our thesis, we intend to lay out the linguistic and didactic foundations necessary for the future elaboration of a program or a method in Slavic intercomprehension by taking the example of the Western and the South-Western Slavic languages and in providing a linguistic analysis of three languages: Czech, Slovene and Croatian.In our work, we seek mainly to provide two elements:- A series of linguistic hypotheses aimed at determining the points to be taught in an intercomprehension method concerning Czech, Slovene and Croatian;- A presentation of programs and support in intercomprehension didactics realized and tested as part of our curriculum.In our work, we find that the didactics of Slavic intercomprehension differs in many ways from classical learning. In the case of intercomprehension, many points that are normally heavy and complex to master may be only passed through quickly.Thanks to our linguistical and didactical analyzes, we have been able to provide a reflection on one of the forms that Slavic intercomprehension formation can take in the future. We particularly recommend the use of online resources, for example via the website www.rozrazum.eu, developed as a part of this thesis to test activities following the methodology made for Eurom 5 (Bonvino et al., 2001). This website can initially be used as a test and development platform for didactical approaches, while being functional, and therefore available to a public of learners.