Pension funds are the principal sources of retirement income for millions of people in the world. Pension funds are also important contributors to the gross domestic product (GDP) of countries. This study focuses on pension funds in Kenya. Retirement income accounts for 68 percent of the total income of retirees in Kenya, while pension assets account for 30 percent of Kenya’s GDP. It is therefore important that pension funds be managed effectively, not only in Kenya, but also in other countries. The primary objective of the study is to investigate ways of enhancing pension fund efficiency by establishing the determinants of such efficiency. More specifically, the study explores the effect that the organisational culture, regulations, investment strategy, ethics, risk management, design, size and the age profile of members of pension funds exert on the efficiency of these funds. A sample of 749 pension funds was drawn from the Kenyan Retirement Benefits Authority (RBA) register. The sample selection was based on the criterion that these pension funds should have been in existence within the period 2001 to 2008. Seven hundred and forty-nine (749) questionnaires were mailed to the trustees of these pension funds. Three hundred and sixty-two (362) usable questionnaires were returned, which translated into a response rate of 48.3 per cent. Except for financial efficiency, self-constructed instruments based on secondary literature reviews were used to measure the variables in the hypothesised model to improve pension fund efficiency. Appropriate steps were taken to ensure the validity and reliability of these measuring instruments. The empirical results revealed that leadership, governance, regulations, design, membership age and size of funds had no significant influence on operational efficiency of these funds. The results further showed that the membership age, design, regulations and operational efficiency of pension funds exerted no significant influence on their financial efficiency. The results also revealed that the membership age, size and design of pension funds did not influence how these funds were led by their leadership. iv The empirical results however showed that smaller pension funds were perceived to exhibit better financial efficiency, while pension funds with membership aged 31 - 40 were perceived to be better governed compared to other age groups. Finally, in rigorous structural equation analyses, no significant relationships were found between fund regulations (independent variable), on the one hand, and fund governance and leadership (dependent variables), on the other hand. Use of simple linear regression however disclosed a significant positive relationship between the afore-mentioned independent variable and dependent variables.