This paper examines one aspect of early twentieth century debates over the meaning of scientific methodology and epistemology within the social sciences: the tendency of sociologists to invoke “laboratory” as a multivalent concept and in reference to diverse institutions and sites of exploration. The aspiration to designate or create laboratories as spaces of sociological knowledge production was broadly unifying in early American sociology (1890–1930), even though there was no general agreement about what “laboratory” meant, nor any explicit acknowledgment of that lack of consensus. The persistence of laboratory talk in sociology over decades reflects the power of “laboratory” as a productively ambiguous, legitimizing ideal for sociologists aspiring to make their discipline rigorously scientific.