The vast infrastructure financing needs far exceed the fiscal capacity of governments and balance sheets of multilateral development banks. Notwithstanding the extensive private financing that can potentially be attracted, current participation of private capital in Asian infrastructure is quite low. Private financing is still predominantly provided by the banking sectors with the large Asian institutional investor pool untapped.

There is a significant need for AIIB to play a catalytic role to increase private and other investors’ appetite for investing in emerging market infrastructure as well as other productive sectors that are associated with and complementary to core infrastructure. This becomes even more important at times of increased financial distress and economic downturns when private capital withdraws from developing countries. AIIB's financing can be direct or indirect, with flexibility in how financings are structured. Investment may take a variety of forms, including loans, guarantees, or equity investments.