Illich’s Tools for Conviviality argues that modern societies are dominated by industrial tools that no longer serve human purposes, but instead reorganise human life around institutional productivity, dependency and control. His central distinction is between convivial tools and manipulative industrial systems. Convivial tools enlarge personal competence, creativity and mutual dependence; industrial tools, when they exceed appropriate limits, reduce people to consumers, clients or operators within systems they cannot meaningfully govern. Illich’s critique is not a rejection of technology as such, but a demand for politically defined limits on tools so that they remain subordinate to human freedom. His examples of medicine, schooling and transport show a recurring pattern: institutions initially solve real problems, but eventually cross a “second watershed,” after which further expansion produces counterproductive effects. Medicine creates iatrogenic illness, schooling manufactures dependence on certification, and transport systems generate distance, congestion and compulsory speed. Against this escalation, Illich proposes convivial reconstruction, a social order in which tools are accessible, understandable and usable by ordinary people without professional monopoly. The bicycle, the telephone and simple hand tools exemplify technologies that can support autonomous action rather than institutional domination. His conclusion is ethical and political: a just society cannot be measured by maximum output, but by whether people retain the capacity to shape their own lives, cooperate freely and use technology without becoming enslaved by it.