-We develop and test a theory of the origins of network
structures, specifi cally of structural holes, building and
testing a theoretical framework proposing that network
structures emerge from the interplay of two complementary
forces: structural constraints and network opportunities.
We analyze data on a co-membership network among
501 production teams in the Italian TV production industry
tracked over a period of 12 years, explicitly accounting for
endogeneity. We fi nd that structural holes spanned by
teams originate from the prior status and centrality of
teams that members were part of in the past, in addition
to structural holes spanned in the past. But a focal team
spans fewer structural holes if its members were part of
cohesive teams earlier and if the past teams they were
connected to produced similar artistic content. We also
demonstrate that spanning structural holes is associated
with superior team performance in terms of greater
viewership. The results support both opportunity exploitation
and structural constraint explanations, although we
fi nd that homogeneity rather than diversity influences
performance across structural holes. •