Internal Audit: independent, objective assurance and consulting activity designed to add value and improve an organization's operations. It helps an organization accomplish its objectives by bringing a systematic, disciplined approach to evaluate and improve the effectiveness of risk management, control, and governance processes.
 

Internal Audit Strategy pdf
 

Evaluation: assessment of the relevance, effectiveness, efficiency, impact and sustainability of an activity, project or programme. It is an important source of evidence on the achievement of results and institutional performance. It aims to contribute to accountability by providing evidence of achievements of results, effective and efficient use of resources, as well as organizational learning and decision-making, by providing lessons learned and recommendations for improvement. Other aims include knowledge management and capacity development.
 

ICAO Evaluation Policy pdf
 

Advisory: OIO may be required to provide objective expert guidance and advice to improve ICAO's operations and processes related to governance, risk, management and control. In so doing, OIO shall act solely in an advisory capacity and shall not make management decisions nor assume a management role.