MNE ownership structures are often the result of historical accident or haphazard growth patterns. Where MNEs deliberately incorporate elements of complexity (e.g. lengthy ownership chains, multiple owners at the direct shareholder level, or different locations of direct versus ultimate owners), these are most often dictated by governance rules and risk management, financing, tax, and other institutional or policy-related considerations. Investment policy is one of several policy drivers behind complex ownership structures. The determinants of complexity in MNE ownership structures can be distinguished into two groups. First, there are “endogenous” determinants that are specific to MNEs, either because they are underpinned by operational logic or because they are based on governance or risk management decisions. Second, there are “exogenous” and location-specific determinants that are ultimately based on policy or institutional factors, such as fiscal and financial governance rules and investment policies. Whereas the former group of determinants drives, for the most part, elements of complexity that are the natural or necessary result of the development of a business, the latter group is mostly responsible for complex ownership structures that are purposely created to incorporate entities in specific jurisdictions in the ownership chain between affiliates and parents. The two sets of determinants cannot be seen in isolation. Different determinants tend to operate simultaneously. For example, when MNEs create affiliates or engage in mergers or acquisitions to expand their operations, they consider options to structure such transactions in the most favorable manner from a fiscal and financial perspective. Similarly, when an MNE needs to set up an entity as a vehicle to attract outside financing or as an umbrella entity to house a joint venture with a third party, where possible, it will aim to do so in a jurisdiction that provides an attractive institutional environment.