This thesis was part of DementiaNet, a programme which has been developed to support primary care networks around people with dementia living at home. We explored two preconditions for collaboration in primary dementia care: network leadership and interprofessional communication. Both aspects seemed to be important improvement strategies. We found that network leaders have a positive impact on the network’s quality improvement. However, primary care professionals’ leadership is currently practiced at a basic level. Therefore, we recommended supportive training and coaching. General practitioners and community nurses generally perceived their interprofessional communication as inadequate. They considered mutual trust as the most important facilitating factor for effective communication. Profession-specific factors (e.g., differences in responsibility and profession-specific language) and organizational factors (e.g., lack of shared care plans, no personal contact) negatively influenced communication. Exploratory research revealed that communication structure and nurses’ self-confidence in communication with doctors are favorable targets for improvement of inter-professional communication.