There has been much discussion in recent literature and considerable debate among activists engaged in on-the-ground initiatives regarding how to measure increases in social capital. Measuring social capital starts with conceptual clarity - one must have a clear idea of what it means. Start with a definition:

Social capital is increased when social organization (connectedness) is strengthened, consensus about values grows, common expectations or norms about conduct emerge, and when members of a community accept and seek ownership of their own community life.

I offer below a means for measurement, by developing the concept of social capital as a set of propositions.

Increased social capital is manifested in increased social participation
Among accessible indicators of social participation are voting rates and competition for lower political offices. The same holds for church participation and the non-sectarian associational life in a neighborhood (e.g., clubs). Is participation increasing, decreasing, or steady? In the face of what community-wide trends?

It is also fairly easy to observe neighbors’ participation in and organization of cultural rituals, such as trick-or-treating, caroling, "walking groups" in certain housing developments, housewarmings, block parties, and open houses.

Increased social capital is manifested in resident involvement in public order and security
The robustness and rhythm of street life is a good indicator of residents’ sense of security, and is particularly apparent in the mornings and evenings. Is the street a place to be or a place to be avoided? How do residents respond to trash and graffiti? Documenting this can be as simple as pre- and post-videos.

Information about complaints to the police is telling, especially around issues such as drugs, prostitution, noise, aggressive panhandling, access to and use of public spaces. Is community policing requested or supported? One can also look for the occurrence of community rituals around order, such as "Take Back the Night", the walking groups mentioned earlier, neighborhood watches and block parent participation. It is especially important to learn who complains, who organizes and who participates.

Increased social capital is manifested when residents, neighborhood associations, organizations, businesses, and institutions are linked by stronger reciprocal bonds, including resources outside the neighborhood.
Social networks can be measured by survey instruments that document the existence and quality of linkages between individuals, associations, businesses, agencies and institutions in a neighborhood or community. The Assets Inventory, developed by the Alliance, is one such tool that has been nationally normed. Repeated Asset Inventories can be used to show changes in the variety as well as the quality of social relationships used by individuals in their adaptations to community life.