A structural interpretation of institutionalism has become dominant in public management research. Yet, studies tend to assume an institutional-level phenomenon without specifying how an organizational field was identified or whether structural characteristics can indeed be found in the organizational population studied. This lacuna is illustrated by exploring the structural interpretation of the field construct in the case of the recent overhaul of English primary care. Findings demonstrate the need for a more robust application of institutionalism in empirical research. Possible research problems for public management and a future research agenda based on a more relational approach to fields are discussed.