More and more connected systems are entering the social and shared home environment. Interaction with these systems is often rather individual and based on personal preferences, leading to conflicts in multi-user situations. In this paper, we aim to develop a perspective on how to design for multi-user interaction with connected lighting systems, based on a better understanding of real-life interpersonal lighting conflicts. In order to understand everyday lighting conflicts, including their causes and resolution strategies, we present two studies. First, we observe real-life lighting conflicts between couples living in single-room apartments. Using probes for data gathering followed by dyadic interviews, we identify the role of agreements on use in conflicts and we identify different types of conflicts (preference, activity, and attitude conflicts). Next, we take a more disruptive approach based on technology probes, where we provoke lighting conflicts in family living rooms to observe resolution strategies. We find that people try to avoid conflicts at all costs. If there is a risk that others are negatively affected by an adjustment, people rather not interact with the system at all. Based on these insights, we defined a perspective on designing for multi-user interaction that provides the user with the confidence that interactions are socially accepted. This assurance can be given by presenting the user with information leading to awareness about the acceptance of a lighting change by the other users. We advise on what information can be visualized, based on the three conflict types we observed in the study. The combination of a deeper understanding of conflicts and a perspective on multi-user interface design can serve as a starting point to design better multi-user interfaces for domestic connected systems.