By the late 1930s, silicosis had become one of the most important occupational diseases in Chile. It was a medical and scientific problem, and a favorite topic in medical congresses; in Chile, a mining country, it also had serious political and economic implications. The recognition of silicosis did not happen in a vacuum, but was part of a national debate on the social role of the state and its responsibility toward working people's health and safety. This article traces the history of silicosis as an occupational disease from the late 1930s to the late 1960s, and argues that the recognition of the disease was the result of a medical, labor, and political struggle.