Interacting: Interactions of some sort are a pre-requisite for associations. Two “friends” are hardly friends if they opt never to interact with each other when they could. Within large collectives, of course, many members won’t know or interact with each other at all. But, each member must interact with some other member for them to count as a member and for their collective to count as an association. Interactions are also a domain of interpersonal engagement unto themselves apart from associations. Our average day is full of incidental interactions with strangers and non-associates, on buses, in the streets, in parks with children, and in buying milk from the local shop. These micro-moments of connection constitute a significant portion of our experience of living together with other people (Fredrickson 2013: Part I; Speck 2012: 49; Cacioppo &amp; Patrick 2008: 237). While philosophers tend to focus on larger-scale, substantive and active forms of association, they have reason to analyze as well the ambient sociability (or lack of it) that is available to us within our general environment, and the ways that our incidental interactions (or lack of them) can resonate with the rest of our associational life. For example, the phenomena of “neighborhood effects” on voting behavior, our attitudes to strangers, and our own self-esteem, are important in thinking about the associative value in our routine connections that fall short of thicker forms of association (Sampson 2011). These interactions and the incidental communities they create provide resources that can build up to, and support, the more substantive goods that flow from meaningful association (Fleischacker 1998: 273; Fredrickson 2013: Part II). Importantly, the quality and number of these incidental micro-interactions is subject partly to our control. We limit our opportunities for such moments if, for example, we choose to shop online, to commute alone in our car, or to retreat into a gated community with vigorous vetting processes for residents.