This is a book about patterns for resource management in software systems. The patterns provide solutions for problems that are typically encountered by software architects and developers when trying to provide an effective and efficient means of managing resources in a software system. Efficient management of resources is critical in the execution of any kind of software. From embedded software in a mobile device to software in a large enterprise server, it is important that resources, such as memory, threading, files, or network connections, are managed efficiently to allow the systems to function properly and effectively.