This thesis seeks to examine and evaluate a selection of current approaches to historical syntax by focusing on the study of a particular linguistic event, the development of the modal verbs in English. It begins with a description of the properties of these elements in earlier stages of the language. Chapter 2 introduces several theoretical concepts which will be useful in understanding some of the explanations proposed for the development of the modals, and Chapter 3 summarizes these explanations. The thesis concludes with a look at the study of diachronic syntax in general and a discussion of the problems and biases of the various approaches and the effects of one's theoretical framework on endeavors in the field.