This publication addresses the main challenges related to the sustainable operation and effective utilization of a research reactor. Clarity on the vision, mission, and purpose of a research reactor is directly related to understanding the optimization of its availability and reliability. The practices of interest discussed are generally within the domain of the research reactor operating organization and involves operating activities and management systems. The scope includes the attributes of different management systems, related practices and the activities that have proven their value through demonstrated performance excellence in several Member States. It provides a high-level summary of the key activities supporting availability and reliability, provides examples of good practices of operating research reactors in Member States, and references to additional IAEA publications, where applicable, for more comprehensive details. This publication is intended for research reactor designers, operators, regulators, and other stakeholders as guidance for improving operation and maintenance practices of research reactors.