This paper explores the investment management structures of institutional investors in Kenya. The investment management approach of three main categories of institutional investors with significant activity in the market, namely, unit trusts, retirement benefits funds and insurance companies is investigated. The choice of the investment management structure is a critical first step in the investment decision making process of an investor. Using desk top analysis of various reports and key informant telephone interviews, the research identifies two main investment management structures being used by these institutional investors. The study uses a random sample from among the entities in each category. In house investment management structure where part or the entire portfolio of assets is managed by internal teams was found to be in use by 20% of insurance companies. No unit trusts used this approach but one retirement benefits scheme was found to manage part of its assets internally. As a means to comply with regulations, virtually all retirement benefits funds used delegated investment management model. Delegation among pension funds took the form of separately managed accounts (SMA) and guaranteed funds. 80% of Insurance companies delegated investment management through SMAs. This paper recommends the relaxation of compliance based rules on investment management to allow fiduciaries exercise greater control and discretion in the selection of investment management approaches.