The goal of this project was to understand how migrants and other refugees make decisions regarding onward migration, stay, or return in Greece and Turkey. We used a mixed-methods approach of a migrant to migrant survey and qualitative interviews. This case study explains the steps taken in the research practicalities to implement the project including the selection and training of fieldworkers, questionnaire programming, and survey checking. As refugees and other migrants are a vulnerable group, the informed consent process and the use of reciprocity within this study are discussed. The research analysis explores how the mixed-methods approach brought forth different components of the results. In the conclusion, key results and lessons learned are explored.