Use established concepts from existing procurement and collaboration literature

N/A

Interview the key person from each social enterprise

Interview more than one person from case organizations whenever possible

Use multiple data sources for triangulation

Transcripts are shared with informants for verification

Establish a chain of evidence (e.g. protocol, interview overview, coding tree) so that conclusions are linked with data presented

Sampling from a single country to control the influence of institutional context

Based on the literature review to establish a theoretical anchor before data analysis

Report case selection criteria

N/A

Illustrate the coding process and present the coding tree (Figure 1)

Do pattern matching through within- and cross-case comparison

Use figures to assist in explanation building

Sampling from the Netherlands where results can be generalizable to other economic domains

Use replication logic in the multiple-case design (literal replication + theoretical replication)

Select multiple cases from different social enterprise models to encourage broader applicability

Select multiple cases within the same models

Provide the case overview (Table 1) that clearly describes case organizations and contextual factors

N/A

Thick description of research context and findings that allow reader to assess the transferability

Compare findings with extant literature to outline contributions

Explain research question and theoretical positioning clearly

Develop an interview protocol ( Appendix 1) that aligns closely with the research question

Select cases based on purposive sampling from three common social enterprise models

Send the interview protocol to interviewees before interviews

Record interview data and develop a case study database

Involve authors who did not collect data to ensure the objectivity of the interpretation

Conduct independent coding checks for reliability