A key theme in capital markets research examines the relationships between accounting information and firm value. Two concerns relating to the value relevance of accounting information are: (1) concerns over the explanatory and predictive power of the evidence presented in the prior literature (Lev, 1989); and (2) the evidence of a deterioration in the association between accounting information and stock prices over the past four decades (Collins, Maydew and Weiss, 1997; Francis and Schipper, 1999; Lev and Zarowin, 1999). These concerns provide the key motivation for this thesis which examines: (1) the usefulness of the clean surplus accounting equation in valuation; (2) the role of accounting information in estimating and predicting systematic risk and; (3) the changing nature of the relationship between accounting information, stock prices and risk over time. The empirical research provides evidence of the value-irrelevance of the clean surplus equation and that controlling for the functional form of the earnings-returns relationship is more important. Evidence is also provided that accounting variables are highly associated with M-GARCH risk betas and also possess predictive ability relative to these risk measures. Finally, the relationships between stock prices, risk models and accounting information are shown to have not deteriorated over time, contrary to prior evidence. Rather, the functional form of the relationship has changed from linear to a non-linear arctan association. Overall, accounting information continues to play the central role in the determination of stock prices and risk metrics.