The issue of the professional integration of handicapped workers is generally dealt with from the perspective of measures to encourage initial and life-long training, labour-market entry and ergonomic workplace adaptation. We offer here a qualitative analysis of the professional practices of blind and deaf wage-earners in order to highlight some less familiar aspects of integration, particularly over time. Specifically, on the basis of a study conducted in a large company, using the perspectives of anthropology and labour sociology and drawing on the concepts of representations and competences, we describe the chaotic processes by which visually and aurally impaired workers manage to exit from dependency, or on the contrary are thrown back into it. The analysis focuses in particular on technical and organisational change and emphasises their ambiguous effects on skill learning and development.