Organisation’s adaptation to owner’s chronic illness is an important theme for all businesses, but it is especially valuable for small family businesses as well as entrepreneurial couples due to their strong interrelation between family and business. So far family business research has not looked into family businesses’ process of adapting to the disruption caused by the occurence of owner’s severe chronic illness. The purpose of this thesis was to look at what impact an owner’s severe chronic illness has on the organisation’s adaptation. To fulfil the purpose, this study combines family science, and family business research and theories in an interdisciplinary manner, applying family science theory to family business research. Our approach is directed by the Double ABCX Model of Family Stress and the FAAR Model to explore the adaptation process of family businesses and to identify demands and resources connected to the disruption.

This multiple case study, utilising semi-structured interviews, observations and secondary data was conducted in a Finnish and German context. The collected qualitative data is presented as narrative case summaries, and analysed by applying in- and cross-case analysis. The findings add to the theoretical understanding of the adaptation process by identifying preconditions, which affect organisations’ adaptation process. Moreover, we identified demands that a chronic illness causes for both the business and the family as well as resources that are used to respond to the new demands. A model illustrating the adaptation process and its dimensions is presented. The findings of the study do not only serve family businesses coping with a chronic illness but provide more implications for businesses in general. Organisations can use the study’s findings to prepare and make their business fit for disruptions of different nature. In addition, organisations in the particular situation researched can benefit by better understanding how they could further improve to stay resilient for possible future disruptions.