Objectives: The correlation between quartz dust concentrations in the Swiss enterprises and the incidence of silicosis and other related diseases acknowledged as occupational diseases (OD) was investigated. Material and Methods: Quartz dust concentrations were obtained from Suva’s databases of occupational health surveillance measurements between 2005 and 2014. Information on quartz dust-related diseases was from medical dossiers of workers with OD acknowledged by Suva between 2005 and 2014. Results: The median quartz dust concentration of the 2579 measurements between 2005 and 2014 was 0.09 mg/m³ (alveolar fraction). Out of all measurements, 28% were above the Swiss occupational exposure limit (OEL) of 0.15 mg/m³ (alveolar fraction). One hundred eighty-one individuals suffered from acknowledged quartz dust-related disease (179 silicosis and 2 chronic obstructive pulmonary disease (COPD)). Additionally, 8 out of these workers were diagnosed with lung cancer and 55 with COPD of a non-specified cause. Out of all workers, 46% were exposed to silica dust for the first time before 1975 when the current Swiss OEL was introduced. Out of the foreign workers, 63% began to work abroad, during which they could have at least partly acquired their silicosis. Out of all workers, 75% were ever-smokers. Conclusions: The incidence of silicosis decreased drastically from approximately 300 cases/year in the 1970s to fewer than 20 cases/year 20 years ago. Several findings of this study that could help to interpret the ongoing occurrence of the disease include excessive exposure in or outside of Switzerland in former or current times, vulnerability to the development of silicosis due to cigarette smoke, or poor compliance with wearing breathing masks. Int J Occup Med Environ Health 2018;31(5):659–676