Introduction: There is a need for individualized discharge planning to support frail older persons at hospital discharge. In this context, active participation on their behalf cannot be taken for granted. The aim of this study was to elucidate patient participation in discharge planning conferences, with a focus on frail older persons, supported by the theory of positioning described by Harré & van Langenhove. Methods: The study was designed as a case study based on audio-recordings of multidisciplinary discharge planning conferences and interviews with health professionals elucidating their opinions on preconditions for patient participation in discharge planning. The analysis has been performed using qualitative content analysis and discourse analysis. Data collection took place during 2008–2009 and included 40 health professionals and 13 frail older persons in hospital or municipal settings. Results: Findings revealed four different positions of participation, characterized by the older person’s level of activity during the conference and his/her appearance as being reduced (patient) or whole (person). The positions varied dynamically from being an active person, passive person, active patient, or passive patient and the health professionals, next-of-kin, and the older persons themselves contributed to the positioning. Conclusions: The findings showed how the institutional setting served as a purposeful structure or a confinement to patient participation.