In order to address new demands from citizens and companies, public agencies are developing new ways of delivering public services within a multi-channel logic. In this context, Citizen Shops have been designed to increase speed of response, to simplify procedures and, above all, to improve service quality. This article aims to evaluate the perceptions of users of public services in order to improve their quality. The article follows a marketing perspective, paying special attention to citizens' expectations and perceptions and to the role of emotions in the encounter. Given the nature of the research issue, the investigation followed a case-study methodology. The authors present an adaptation of the Critical Incident Technique and analyse extensive qualitative and quantitative data collected in six Portuguese Citizen Shops. The findings show that expectations are extremely dynamic and play a relevant role in users' satisfaction. Satisfying and neutral attributes were identified, and the Critical Incident Technique also revealed the importance of emotions in the encounter.