Business change, whether planned or unplanned, must be managed if the organization is to benefit. This guide explains how to manage the key components of business change - the organization, its people, the technology and the external business environment. It also describes the process of managing business change, from the strategies behind it through to new ways of working and the realization of benefits. There is also advice on managing the "people" issues, which typically consume 80 per cent of the resources required for business change. This guide outlines the programme management process described in detail in the companion OGC guidence on PRINCE and Programme Management and Risk.