In intuitive terms to be sharpened below, the micromorphology hypothesis is the hypothesis that an affix can itself be morphologically complex. This is a widespread assumption in descriptive accounts of the morphology of individual languages; yet, with only the rarest exceptions (e.g., the proposals of Bauer 1988; Bochner 1992 and Luís & Spencer 2005), morphological theory has tended to reject this hypothesis, most often tacitly. My objective here is therefore threefold. I begin by characterizing the micromorphology hypothesis in more precise terms, exemplifying it with the analysis of nominal inflection in Noon (Niger Congo/Atlantic; Senegal) presented by Soukka (2000) and showing that in a rule-based conception of morphology, this hypothesis entails an operation of rule conflation similar (though not identical) to the operation of function composition in mathematics. I propose an inferential realizational morphological theory that implements the micromorphology hypothesis by incorporating the notion of rule conflation. I demonstrate its basic properties with regard to the Noon evidence. I survey several kinds of evidence that favor the conciliation of morphological theory with the micromorphology hypothesis and therefore necessitate a rather profound rethinking of the principles of morphotactics. I discuss a number of apparent morphotactic anomalies that can be readily accounted for by assuming that the default patterns of interaction among a language’s morphological rules can be overridden by the conflation of two or more rules. I conclude by discussing the wider implications of the micromorphology hypothesis for refining a theory of inflectional exponence, observing that rule conflation is only one of the ways in which current conceptions of the algebra of morphotactics must be improved upon.