Supporting family caregivers has been identified as a high-priority health goal worldwide. To reach this group, low-threshold, flexible, and accessible support services are needed that are individually adapted to the needs of the affected families. The newly developed digital counseling service “Alles Clara” intends to provide support for this group by connecting them with healthcare experts, allowing for professional and individual counseling at any time and place. To demonstrate the impact of Alles Clara and to be able to further develop and improve the service, it is to be evaluated. To uncover what works, how, under which conditions, and for whom, we drew on the realist evaluation methodology to devise an initial program theory. In this article, we describe the development of and present the initial program theory of Alles Clara. Internal program documents and guided individual interviews with stakeholders and counselors served as data sources to gradually develop a preliminary understanding of Alles Clara’s intended impact and modes of action in an iterative process. The initial program theory outlines central chains of events, mechanisms, and outcomes of the digital service. Family caregivers experience relief through expanding awareness, appreciation, trusting relationships, and reflection. For professionals, a new professional environment, a healthful culture, quality, and meaningfulness affect job satisfaction. Central to unfolding its mechanisms is that the digital counseling service enables an experience of “being seen” while “not being seen.” The results provide information about the impact of Alles Clara on both the target groups, identify possible areas for service improvement, and serve as a basis for evaluation and regular monitoring, especially, when it comes to the question of whether and how digital services can be supportive in the sense of a person-centred orientation of health care.