This study represents a bold reanalysis of the phonemic system of Germanic consonants. The accepted primary voiced-voiceless phonemic contrast is replaced by fortis-lenis, whose origin is projected back into Proto-Germanic. It is proposed to view the Germanic consonant shift as the result of lenition in Gmc. /b d g f X s X/ and of strengthening of articulation in Gmc. /p t k/. Voice and spirantization are characteristic of the lenis members, whereas voicelessness and extraduration are characteristic of fortis. This concept, backed by orthographic, comparative and acoustic phonetic data, supplies not only a simpler and more plausible development into the daughter languages, but also provides a common element in the explanation of the First and Second Sound Shift.