Case management is a program expected to improve the quality of care for frail, community dwelling older people and thus, their quality of life. However, the heterogeneity, the multidimensionality and complexity of these programmes call for innovative evaluation means. Our aim was to propose a realist perspective, enabling the identification of mid-range theories linked to the drivers of success of case management. Starting with a realist synthesis of case management in other countries, we examined in-depth how and why case management could be effective in Belgium for this population, by the means of a multiple, embedded case study among the Protocol 3 projects. We identified crucial components explaining the success of case management and these components enabled us, in turn, to propose three types of case management. The type of case management should be linked to the complexity of the situation of the older person but certainly also linked to the local context.(SP - Sciences de la santé publique) -- UCL, 201