Purpose - The purpose of this paper is to show that numerous studies have advanced social capital research over the past decade. Most studies have accepted the theoretical distinction between bonding and bridging social capital networks. Many, however, tend to agglomerate empirical research under the one catch-all social capital concept, rather than classifying it according to the bonding/bridging distinction. Furthermore, most studies make little distinction on the basis of methodology, between qualitative and quantitative approaches to investigating social capital. These omissions need to be addressed. Design/methodology/approach - This paper reviews definitions and applications of bridging and bonding social capital, classifies empirical studies according to each network type, and produces a further breakdown according to methodological approach. Findings - The result is a four-part "grid" of social capital research, encompassing bonding and bridging, and quantitative and qualitative aspects. This paper finds that most qualitative research examines non-excludable and excludable goods and is relevant to bonding social capital, whilst most quantitative analysis looks at civic networks and norms of trust, and relates to bridging social capital. Research limitations/implications - Results advance the task of clarifying and measuring social capital. Practical implications - Further development of the bridging/bonding social capital conceptual pair should allow for a more precise measurement of a community, or region. Originality/value - No review paper to date captures the above empirical and methodological "grid" clearly. [ABSTRACT FROM AUTHOR]