The transformations in West German architecture between 1949 and 1959 were fast-paced and comprehensive, its idiom moving away from the light, filigree style of the early post-war period towards the robust, material expression that characterized International High Modern Architecture from the mid-1950s onwards. Despite the pace and intensity of these changes, however, they cannot be ascribed to a singular rhetorical program or movement. Instead, they represent the interplay of architectural expression and building construction developments, both influenced strongly by contemporary American precedents exported to West Germany through official and popular channels. The work of Hans Schwippert and Sep Ruf, friends and professional affiliates throughout the period studied, offers important insights into the pathways these transformations took through rhetoric, construction, reception and architecture expression. The comparison of these two architects’ construction practices and architectural expression is underpinned by an analysis of three decisive documents, which describe the changing manner in which West Germany defined its self-image through architecture between 1949 and 1959.