The paper investigates the extent to which the emerging notion of "social capital" is analytically treatable within a microeconomic approach, and what the consequences, in terms of results achieved by microeconomic tools, are. First, after a critical examination of the recent socioeconomic literature on Social Capital, a microeconomic-grounded definition, shaped around the
elements of reciprocal trust and voluntary cooperation, is provided. Secondly, the implications of the definition, which attempts to synthesise the key micro issues of social capital as it is usually presented, are then discussed. Consequently, a model rooting on elements of mixed-public good, non-cooperative agreements and dynamic optimal control is constructed and presented. Finally, the set of possible model extensions and main critical points are sketched. The concluding section also sheds light on the directions of our future research.