This thesis considers the appropriate methodology for constructing a theory in accounting and investigates the nature of the basic assumptions needed for constructing the theory. The thesis is divided into three main parts. Part I deals with methodological issues in theory construction. This discussion involved Chapters Two and Three. Chapter Two considered the nature and structure of empirical theory. Chapter Three considered the relevance of the concepts discussed in Chapter Two to accounting theory formation. Part II is devoted to an investigation of the nature of the basic assumptions upon which accounting rests. As accounting is concerned with the measurement and communication of data revealing economic activity of an entity, the basic assumptions needed will necessarily include measurement and communication assumptions. We investigated accounting measurement and communication to determine the areas in which basic assumptions are necessary to facilitate the measurement process and the transmission of information. The discussion involved Chapters Four and Five which dealt with measurement assumptions and communication assumptions respectively Part III is devoted to an examination of one of the sets of basic assumptions offered by accounting theorists in the literature. Our examination involved two aspects related to the two previous parts: we examined the methodology employed (Part I) and investigated whether the set of basic assumptions dealt with the areas in which basic assumptions are necessary.