Add to ORKGOver the past decade social capital has matured from a concept into a field of research. We identify some of the main theoretical developments over this period and point to some areas where further work appears warranted. We argue that the basic social capital thesis has now been widely accepted across a range of disciplines and fields, and that research is therefore naturally shifting toward more specific aspects and mechanisms. Social capital has been a “growth industry” (Baker & Faulkner, 2009). As Figure 1 shows, the use of “social capital ” in the title, abstract, and key words of journal articles has multiplied rap-idly over the past several decades. In our 2002 article (Adler & Kwon, 2002) we argued that so-cial capital was s...