The Complaints-resolution, Evaluation and Integrity Unit (CEIU) was established in 2016 as an independent unit within AIIB and is part of AIIB’s Oversight Mechanism created by its Board of Directors under Article 26(iv) of the AIIB Articles of Agreement. This provision empowers the Board to supervise the management and the operation of the Bank on a regular basis, and establish an oversight mechanism for that purpose, in line with principles of transparency, openness, independence and accountability. CEIU is led by a Managing Director who reports directly to the Board.

The primary responsibilities of CEIU are to (i) selectively assess the quality and results (for completed projects) of the Bank’s ongoing and completed investment portfolio, (ii) serve as the focal point for external requests or complaints regarding compliance with AIIB’s Environmental and Social Policy (ESP) under the Project-affected People’s Mechanism (PPM) Policy, and (iii) investigate project-related fraud and corruption cases under the Policy on Prohibited Practices.

Complaints-resolution. The Project-affected People’s Mechanism (PPM) is the complaints-handling mechanism established and implemented by CEIU to conduct an independent and impartial review of complaints from Project-affected People who believe they have been or are likely to be adversely affected by AIIB’s failure to implement its Environmental and Social Policy (ESP).

Evaluation. CEIU’s independent learning and evaluation function contributes to continuous improvement as part of the Bank’s corporate and learning culture. In accordance with AIIB's Learning and Evaluation Policy, CEIU evaluates AIIB’s ordinary and special operations and determines whether these projects and processes are producing the expected results and delivering the value expected. CEIU also shares lessons with AIIB staff and peer institutions.

Integrity. Under its integrity function, CEIU carries out anti-fraud and corruption work in accordance with AIIB’s Policy on Prohibited Practices (PPP). This includes investigating and handling allegation relating to Prohibited Practices.

CEIU also provides independent input to AIIB’s President when Management formulates and/or reviews policies and strategies.

The PPM is a member of the Independent Accountability Mechanisms Network (IAMnet). IAMnet is “a virtual network of dedicated practitioners who contribute to the regular exchange of ideas and assist with institutional capacity building in accountability and compliance as components of corporate governance.”

IAMnet includes the accountability mechanisms of multilateral development banks. Participation in IAMnet allows for exchange of IAM good practices and strengthening of collaboration on institutional accountability and compliance.

In December 2022, AIIB became an International Institution Observer of the OECD DAC Network on Development Evaluation (EvalNet). EvalNet is an international forum of evaluation managers and specialists from development co-operation ministries and agencies in OECD DAC member countries and multilateral development institutions. EvalNet supports collaboration and communication of evaluation findings and has had an instrumental role in developing key international norms and standards for development evaluation. These are reflected in AIIB’s Learning and Evaluation Policy (2021). CEIU continues to participate in EvalNet-related activities, including its annual and other meetings, and those of the COVID-19 Global Evaluation Coalition.

AIIB participates in the Conference of International Investigators, “a forum for investigators of international organizations to exchange ideas, discuss integrity issues, address challenges in fighting fraud and corruption, receive new developments and share leading practices.”