OBJECTIVE: This multiple case study investigated support and process in the Individual Placement and Support (IPS) approach from individual client, longitudinal, and Person-Environment-Occupation (PEO) model perspectives. PARTICIPANTS: Five IPS-participants, or cases, with Severe Mental Illness (SMI) who worked a minimum of 4 hours a week entered the study. METHODS: A multiple data collection method was used over a period of 12 months and included IPS-vocational profiles and plans as well as various instruments and questionnaires concerning socio-demographics, work performance, limitations, and accommodations. Both within-and across-case analyses were performed. RESULTS: The IPS-process concerned job search support, job-matches (PEO-match), and adjustment of the PEO-match by providing accommodations by on-and off-worksite support. All participants had limitations concerning social interactions and handling symptoms/tolerating stress. Several accommodations were made for the same limitations, mostly directed towards the social environment. Prior work experience, disclosure, and not being in an acute phase of illness seemed important to the support provided. CONCLUSIONS: This study has visualised the support and process in IPS and provided a theoretical framework, the PEO-model, to detect limitations and provide IPS-support. The organization of IPS-support and methods of providing it to individuals may be important for job tenure and employment success.