Background: Informal supportive networks of individuals with intellectual disability have become increasingly important. The aim of this paper is to describe how the Family Network Method--Intellectual Disability (FNM-ID) offers a way to gather the perspective of people with mild intellectual disability on their family support. Method: The FNM is designed to explore how individuals define their family contexts, and more specifically how they perceive existing supportive relationships in these contexts. Results: By carefully piloting ways of questioning people with mild intellectual disability, systematic adaptations were made to the original FNM. Data obtained by the FNM-ID can be analysed using social network analysis. Thereby, the FNM-ID provides rich, theoretically significant information on emotional support in the family networks of individuals with mild intellectual disability. Conclusions: The FNM-ID is a useful and successfully adapted tool for other researchers and professionals to systematically explore the family support experiences of individuals with mild intellectual disability.