Domestic service robots are nowadays widely available on the consumer market. As such, robots have begun entering people’s homes and daily lives. However, it seems that the dissemination of domestic robots has not happened as easily and widespread as it was anticipated in the first place. Little is known about the reasons why because long-term studies of ordinary people using real robots in their homes are rare. To better understand how people interact, use and accept domestic robots, studies of human-robot interaction require ecologically valid settings and the user and their needs have to come into the focus. In this dissertation, we propose to investigate the dynamics of human-robot interaction in domestic environments. We first explore the field by means of a 6-month ethnographic study of nine households. We provided each of the households with a Roomba vacuum cleaning robot. Our motivation is to understand long-term acceptance and to identify factors that can promote and hinder the integration of a domestic service robot in different types of households. We would like to find out how people’s perception of the robot, and the way they interact with it and use it, evolve over time. Furthermore, as social factors were highlighted in previous studies on technology adoption in homes, we shed light on to what extent people view Roomba and other types of domestic robots as a social entity and to what extent they anthropomorphize it. Findings of this research can be used to guide the design of user-oriented robots that have the potential to lastingly become a valuable part within the home ecology. Then, we pursue the idea of developing our own domestic robot prototype that could be used in a household with children. We imagine a playful robot that aims to motivate young children to tidy up their toys. In a first evaluation of the robot in 14 family homes, we study the effect of a proactive and reactive robot behavior on children’s interaction with the robot and their motivation to tidy up. A follow-up experiment explores the possibility to sustain children’s engagement by manipulating the robot’s behavior in such way that it appears unexpected. We further investigate how far this influences children’s perception of the robot in terms of anthropomorphism. Our findings emphasize the importance of research in ecologically valid settings in order to obtain a better understanding of human-robot interaction, advance further the design of user-oriented robots and foster the long-term acceptance of these devices.