The chapter establishes Germanic as an Indo-European branch by identifying phonological and morphological innovations common to all Germanic languages, e.g. Rask/Grimm’s Law, Verner’s Law and the grammation of a complex verbal system with strong, weak and preterite-present verbs. Furthermore, the chapter identifies three Germanic sub-branches (East, North, West) and discusses the possibility of binary splits leading to intermediary subgroupings, of which either North-West or North-East Germanic seems credible depending on one’s view on Verschärfung. Alternatively, in a dialect continuum, North Germanic may have shared innovations with first East, then West Germanic prior to the final split. Finally, the chapter examines with which Indo-European branches Germanic shares non-trivial innovations and thus, maybe, a common node on the cladistic tree. Promising innovations shared with Italic and with Balto-Slavic (and Tocharian?) are considered in particular, but the sustained productivity of nominal ablaut and the preterite-presents calls for the conclusion that Germanic split off from Proto-Indo-European relatively early, as these features are mostly lost in the non-Anatolian branches.