This thesis aims to contribute to the corporate finance literature by focusing on the interdependence of corporate investment, financing and payout decisions of UK-listed companies, within the period 1999-2008. After the introductory chapter, Chapter 2 critically reviews the existing literature on corporate investment, financing and payout policies. Chapter 3 investigates the interactions among the three corporate decisions. One of the key findings is that the three corporate decisions are likely to be jointly determined in the presence of financial constraints. The results also suggest that the effect of uncertainty on corporate investment is significantly positive, but the effect on dividend payout is significantly negative. Chapter 4 explores the influence of managerial confidence and economic sentiment on the set of jointly determined corporate decisions. An important finding is that the state of confidence at aggregate levels has significantly positive effects on both real investment and debt financing decisions. Chapter 5 discriminates conceptually and evaluates empirically twenty alternative measures of corporate investment used in the existing literature. It is found that conclusions drawn from empirical analysis are likely to be sensitive to the choice of corporate investment measures. The key findings of the thesis are summarised in the conclusion chapter.