Qualitative analysis was used to analyse a diary written over a period of two years by the sister of a dementia patient. The analysis is directed at the question of how a patient and a social network respond to each other during the dementia process. The diary highlights features in the development of the dementia process which receive scant attention in empirical studies: changes in the interaction process between patient and social network; a patient's residual capacities; a caregiver's perceived rewards of caregiving. We designated three phases in the interaction process: the phase of recognition, the stable phase and the phase of destabilization. This diary illustrates how a stable phase in the interaction between patient and primary caregiver can be established. The caregiver derived rewards by noticing and using the patient's residual capacities and by a feeling of being useful. In this case caregiving is not unidirectional. The quality of future support programmes may be enhanced by combining programmes aimed to influence patient's behaviour and to support caregivers.