BACKGROUND: Anxiety and depressive disorders frequently recur, but participation in effective psychological interventions to prevent relapse is limited. The reasons for nonparticipation are largely unknown, hampering successful implementation. The aims of this study were: (1) to investigate reasons why patients with remitted anxiety or depressive disorders refuse cognitive-behavioral therapy relapse prevention interventions (RPIs), (2) to compare these reasons with reasons to participate, and (3) to gain insight into patients' preferences regarding relapse prevention. METHODS: A qualitative study was conducted in which data were gathered from 52 semistructured interviews with patients who either refused or agreed to participate in psychological relapse prevention. The constant comparative method was used. RESULTS: The data showed that those who refused to participate (1) did have knowledge about relapse risks in general, (2) but did not relate this risk to themselves, and therefore, did not feel the need for relapse prevention, or (3) declined to participate for logistical reasons or reasons related to the content of the intervention. Preferences concerning the form and content of RPIs were very diverse. CONCLUSIONS: Psychoeducation on relapse should be provided to patients to help them relate recurrence risks to themselves. RPIs should also be individually tailored.