This volume brings together specialists in inflectional morphology, historical linguistics, and dialectology to explore the processes, directionality, models, and targets of morphological analogy. The chapters draw on atlas data and historical sources, as well as experimental and computational methods, and present case studies from a range of Romance and Germanic languages. Existing work on inferential relationships, predictability, and complexity has investigated what information speakers can access with respect to the shape of inflectional forms; the studies presented here examine how speakers make use of that information and shed light on the properties and contours of inflectional structure. The book is divided into three thematic sections that explore, respectively: the range of objects and patterns that morphological analogy can manipulate; the influence of frequency effects on the choice of models and targets in analogical change; and the mechanisms of change and how these can be modelled. The contributors discuss a variety of significant theoretical issues including the advantages of different models of analogy and inflection, constraints on the choice of template for analogy, autonomous morphology, and non-canonical inflection and morphological complexity. The historical, variationist approaches taken here will complement the considerable existing body of theoretical work in this field and will be of interest to scholars and advanced students working on language change, language complexity, and word structure.