This study investigates the relationship that exists between corporate governance and  firm
performance  of some selected companies listed on the Nigerian Stock Exchange. The intent of
the study is to determine whether corporate governance mechanisms-  CEO duality, board size
audit committee independence, and ownership concentration  have an impact on  firm  performance  surrogated by  return on assets (ROA); return on equity (ROE), profit margin (PM).
It provides empirical evidence  for fifty two (52) non-financial firms in Nigeria for a  period of
2003 to  2008. The  Generalised Least Square (GLS) regression is employed to  examine  the
relationship existing between the variables.  The results reveal  that  board size,  audit committee
independence, ownership  concentration have  a  significant relationship  with return on equity and
profit margin. It  is also observed that  CEO duality has no impact on  firm performance.  The
advocacy is for  the  Securities and Exchange Commission to take into cognisance industry
specific effects before formulating codes of  corporate governance  that determine the characteristic  of the audit committee or the board structure.  Proposition is also made for  the
Corporate Governance Committee  of  companies to  endeavour to do a regular appraisal of their
corporate governance compliance status so as to understand its effect on performance.
Keywords: Corporate Governance, Firm performance, Agency Theory, Agency Costs

Certification----------------------------------------------------------------iii
Declaration-------------------------------------------------------- - - - iv
Dedication ---------------------------------------------------------------- - v
Acknowledgment---------------------------------------------------------- - vi
Abstract------------------------------------------------------------------vii
Table of Contents------------------------------------------------------------ix
List of Figures --------------------------------------------------------------xiv
List of Table -------------------------------------------------------------- - xv

Chapter One: Introduction--------------------------------------------------1
10  Background to the study---------------------------------------------- - 1
11  Statement of Problem--------------------------------------------------2
12  Objectives of Study----------------------------------------------------3
13  Research Questions-------------------------------------------------- - 4
14  Hypotheses---------------------------------------------------------- - 4
15  Scope of Study--------------------------------------------------------4
16  Significance of Study-------------------------------------------------- - 5
17  Limitations of Study----------------------------------------------------6
18  Methodology----------------------------------------------------------6
19  Definition of Terms-------------------------------------------------- - 7

Chapter Two: Literature Review----------------------------------------------9
21  Introduction ----------------------------------------------------------9
22  Conceptual Framework------------------------------------------------ - 10
221  Agency Concept---------------------------------------------------- - 10
222   Corporate Governance Mechanisms for Reducing Agency Costs---------------- 14
2221 Board Size---------------------------------------------------------- - 14
2222 CEO Duality-------------------------------------------------------- - 15
2222 Ownership Concentration------------------------------------------------17
2223 Audit Committee Independence------------------------------------------18
223  Summary of Theory, Hypothesis and Conceptual Model---------------------- - 19
23  Theoretical Framework of Corporate Governance---------------------------- - 21
231  Stakeholder Theory---------------------------------------------------- - 22
232  Stewardship theory---------------------------------------------------- - 22
233  Resource Dependency Theory (RDT)------------------------------------ - 22
234  Agency theory-------------------------------------------------------- - 23
235  Assumptions of Agency Theory------------------------------------------ - 24
236  Limitations of Agency Theory--------------------------------------------25
24  Measuring Firm Performance-------------------------------------------- - 26
25  Measuring Control Variables----------------------------------------------28
251  Company Size----------------------------------------------------------29
252  Leverage------------------------------------------------------------ - 28
26  Corporate Governance and Performance Measures---------------------------- - 29
27  Methodological Review--------------------------------------------------31
28  Corporate Governance Measures in Nigeria----------------------------------32
281  The Role of the Board of Directors, Chairman, and Chief Executive Officer--------32
282  The Role of the Audit Committee------------------------------------------33

Chapter Three: Research Methodology ----------------------------------------34
31  Introduction------------------------------------------------------------34
32  Research Design--------------------------------------------------------34
33  Population of Study---------------------------------------------------- - 34
34  Sample size and Sampling Technique--------------------------------------34
35  Data Gathering Method--------------------------------------------------35
351  Sources of Data-------------------------------------------------------- 35
352  Instruments of Data Collection--------------------------------------------35
353   Validity and Reliability of Instruments--------------------------------------35
36  Data Analysis Method-------------------------------------------------- - 36
361  Methods of Data Analysis------------------------------------------------36
362  Instruments for Data Analysis (Including formulae) ----------------------------36
363  Model Specification---------------------------------------------------- - 37

Chapter Four: Data Presentation and Analysis -------------------------------- 39
41  Introduction----------------------------------------------------------39
42  Data Presentation------------------------------------------------------39
421  Industry Based Presentation----------------------------------------------39
43  Data Analysis -------------------------------------------------------- - 41
431  Summary Statistics------------------------------------------------------41
432  Correlation Analysis----------------------------------------------------46
433  Econometric Analysis----------------------------------------------------47

Chapter Five: Summary, Findings, Conclusion And Recommendations--------------52
51  Introduction----------------------------------------------------------52
52  Summary of Work Done------------------------------------------------ - 52
53  Findings--------------------------------------------------------------53
531  Theoretical Findings----------------------------------------------------53
532  Empirical Findings------------------------------------------------------54
54  Conclusion -------------------------------------------------------- - --55
55  Recommendations------------------------------------------------------55
56  Suggestions for Further Studies---------------------------------------- - - 56

References ---- - ------------------------------------------------------58
Appendices -------------------------------------------------------------- - --66
Appendix 1    Sample Companies and Their Industries------------------------66
Appendix 11   Generalised Least Square Regression Result Of Estimated Model (Fixed
Effects) --------------------------------------------------68