One of the most fundamental organizations of practice for talk-in-interaction is the organization of turn-taking. For there to be the possibility of responsiveness – of one participant being able to show that what they are saying and doing is responsive to what another has said and done – one party needs to talk after the other, and, it turns out, they have to talk singly. It is the organization of the practices of turn-taking that is the resource relied upon by parties to talk-in-interaction to achieve these outcomes routinely: they talk singly – that is, one at a time; and each participant's talk is inspectable, and is inspected, by co-participants to see how it stands to the one that preceded, what sort of response it has accorded the preceding turn. The organization of turn-taking requires a book of its own; all we can give it here is a capsule review, which will appear below. Suffice it to say that the turn-taking organization for conversation works extremely effectively, and produces long stretches of turns-at-talk that follow one another with minimized gap and overlap between them.

A moment's observation and reflection should suggest, however, that turns do not follow one another like identical beads on a string. They have some organization and “shape” to them, aside from their organization as single turns and as series-of-turns (that is, as turns starting with a back-connection and ending with a forward one).