The aim of this study was to describe changes in employment and income following a diagnosis of occupational asthma, and to determine what factors might affect these changes. Two hundred and nine patients with occupational asthma were reviewed on average 3.1 yrs after the diagnosis had been made. They were contacted by telephone or were sent a self-administered questionnaire by post. Multiple logistic regression models were constructed to determine which variables were associated with loss of employment after the diagnosis. At the time of review, 44% of patients had left their previous job and 25% were currently unemployed. Remarkably, 32% remained exposed to the offending agents in the same job. Forty six percent of the patients had suffered a reduction of income (84% of those who had left their employer versus 19% of those still employed in the same company (p < 0.001)). Claims for compensation, size of the company, level of education, and age at the time of diagnosis were significantly associated with a risk for becoming unemployed or having a new employer after the diagnosis of occupational asthma. Occupational asthma results in severe socioeconomic consequences. The French compensation system for occupational asthma should be revised, as the criteria currently used to determine compensation for this disease largely underestimate the social and occupational damages.