This paper considers a distinction frequently used in sociolinguistics and ethnography of speaking to describe speech events: their formality or informality. Three principle meanings of "formality" found in the literature concern whether the formality relates to properties of a communicative code, properties of the social setting in which a code is used, or properties of the analyst's description. Four aspects of formality that apply cross-culturally are: (1) increased structuring of speech; (2) consistency in terms of the social significance of variants chosen at different levels of communicative expression; (3) invoking of positional identities of participants; and (4) emergence of a focus in speech interactions. The role of these variables in cross-cultural comparison and a comparison of certain speech events among the Wolof and Mursi are discussed. All societies seem to make distinctions among speech events according to the four aspects of formality. Comparisons within a society and between societies can be made according to how they connect the various aspects of formality and what concomitant effects formalizing a speech event will have. Formality, in this view, is largely a process of focusing, which can operate along various dimensions. (SW)