The Mattmark tragedy of August 30th, 1965 fuelled the debate in Switzerland, which had already been going on for a few years, regarding the country's largely un­ controlled economic development. This development required ever more foreign labour – especially for big infrastructural projects – including low­skilled labour, which had been abandoned by the Swiss. For the Italian community in Switzerland, the tragedy represented an opportunity to reflect on the meaning of their presence in a country in which they were not accepted and were not well integrated. Using the Mattmark tragedy as a case study, this paper demonstrates how the identitar­ ian construction of Switzerland as a whole, and its relationship with foreigners, is strongly linked to the identitarian construction of the Canton of Valais, where the tragedy occurred. Mattmark represents a major turning point in Switzerland's long and tormented relationship with foreigners: it changed Switzerland's perception of foreigners and of the Swiss themselves and resulted in significant social, media­ related and political changes, especially regarding the subject of safety at work.