This thesis has two (2) broad objectives. The first objective is to test the impact of audit committee and internal audit (IA) function characteristics on IA contribution to the financial statement audit. The second objective is to investigate whether a negative association exists between IA contribution to the financial statement audit and audit fees. The study is conducted in a Malaysian context and focuses on the perspectives of internal auditors. There are a number of motivations for the study. In particular, previous studies have not addressed the need for a better understanding of how corporate governance mechanisms such as audit committee and IA unit attributes may affect IA contribution to the financial statement audit. Also, the results of prior studies on the link between IA contribution to the financial statement audit and audit fees are mixed and inconclusive. Furthermore, there is limited empirical evidence in this area from emerging economy countries, with relatively less developed capital markets such as Malaysia. The underlying theme throughout this thesis is that corporate governance mechanisms i.e., audit committee and IA characteristics have the potential to affect the efficiency of the IA unit thus leading to greater contribution of IA to financial statement audits. Specifically, the thesis argues that certain characteristics of audit committees such as the independence of audit committee members from the management, audit committee members' experience and knowledge in accounting, auditing and finance and their level of interactions with the chief internal auditor have the potential to increase the contribution of IA work to financial statement audits. Likewise, it is also postulated that characteristics of the IA function such as their size and prior experience of their staff in auditing are likely to improve the level of efficiency and hence, encourage greater contribution of IA to the external audit work. Finally, due to the saturation of the audit services market coupled with significant competition among public accounting firms, it is also predicted that the contribution of IA work is increasingly viewed as a potential means of improving external audit efficiency (i.e. by reducing time and effort), leading to lower audit fees. Seven (7) hypotheses are tested in this study based on Malaysian data during 2003. Data collection adopted a multi approach with three (3) key sources of data: a questionnaires survey, in-depth interviews and publicly available data from annual reports. The data collection process involved a mail survey addressed to the chief internal auditors of companies listed on the Kuala Lumpur Stock Exchange (KLSE) Main Board. Five-hundred and two questionnaires (502) were mailed and a total of 101 (20.03%) responses were returned, of which 76 (17.9%) were useable. In addition, in-depth interviews were conducted with 11 chief internal auditors selected from various industries which were also listed on the KLSE Main Board. Finally, publicly available data from annual reports were utilized. The study makes a number of contributions. First, it provides empirical evidence on the impact of audit committee characteristics on IA contribution to financial statement audits. In particular, the study supports a positive relationship between IA contribution to the financial statement audit and three (3) dimensions of audit committee characteristics namely the proportion of independent audit committee members, the extent of audit committee members' experience and knowledge in auditing, accounting and finance, and the frequency of meetings between the chief internal auditor and the audit committee. This suggests that a high proportion of independent audit committee members with experience and knowledge in accounting, auditing and finance is able to enhance the efficacy of the IA function and thus, encourages external auditors to rely more on the IA function. The results support the earlier predictions that more frequent meetings conducted between audit committees and the chief internal auditor leads to higher extent of IA contribution to the financial statement audit. Further, findings of this study also provides support for the positive relationship between the characteristics of the IA function, namely the size of the IA function and the proportion of staff with prior experience in auditing and IA contribution to the financial statement audit. The results suggest that internal auditors contribute more to the financial statement audit when the size of the IA function is larger and when the proportion of IA staff with prior experience in auditing is higher. Finally, the second model tests for a negative relationship between IA contribution to the financial statement audit and audit fees. However, the results did not yield a significant relationship between these two variables. Further clarifications for this result were derived from the interviews with the chief internal auditors. Specifically, it appears that any saving in time and effort due to the contribution of IA to financial statement audits may possibly be used by external auditors to expand their investigations into other more complex areas that require greater attention from them. Other findings from the interviews also suggest that audit committees play an important role as communication facilitators between the IA staff and management, especially by providing a candid forum for IA staff to express their opinions as well as supporting IA staff's recommendations based on their findings during audit investigations. Further, the leadership role of the audit committee also tends to assist the internal auditors to better communicate with management and to ensure that management will act upon the internal auditor's recommendations. In conclusion, the findings may have some implications for regulators and others concerned with establishing guidelines and listing rules pertaining to audit committee effectiveness especially in developing countries. Furthermore, this study also contributes to the literature on how an IA unit's resourcing has implications for IA contribution to the financial statement audit. While the current professional standards (i.e., ISA 610, SAS 65, and AUS 604) view IA as a substitute for external audit, such professional standards also require external auditors to evaluate the quality of IA unit before relying on the work of IA or accept the contribution of IA to the financial statement audit. As such, this study provides evidence on the potential impact that audit committees and IA units may have on such contribution of IA to the financial statement audit.