Maintenance management information systems are essential to ensure control, gain knowledge and improve-decision making in companies dealing with network infrastructure, such as distribution of gas, water, electricity and telecommunications. Divided into three major sections, maintenance management in network utilities defines a series of stages which can be followed to manage maintenance frameworks properly. Different case studies provide detailed descriptions which illustrate the experience in real company situations. An introduction to the concepts is followed by main sections including :- A literature review : covering the basic concepts and models needed for framework design, development and implementation.- Framework design and definition : developing the basic pillars of network utilities maintenance management framework.- Performance evaluation & maturity : focusing on the reliability concept and maturity models from different viewpoints.