This document discusses how insights from information infrastructure theory can help address challenges in developing Spatial Data Infrastructures (SDIs). It argues that SDIs should be viewed as public goods and information infrastructures, rather than standalone systems. Key concepts for understanding information infrastructures that are relevant for SDIs include: viewing them through a socio-technical lens; recognizing the importance of installed bases and path dependencies; understanding the "politics of representations"; and accepting their inherent "messiness". The document illustrates these concepts using examples from efforts to develop health SDIs and eradicate river blindness in West Africa.