Most organisations will have more than one program and/or project competing for the same resources (cash, staff, equipment, etc.) and it is therefore important to identify the relative value of each program or project to the organisation.
The value of the program or project is more than just the costs. It also includes the benefits of the project in a wider business context than just monetary/time costs (e.g. the project could be a key enabler to support future IT developments). Therefore it is important to identify how the program or project fits with the organisation's strategy and objectives as well as the costs, risks, etc.
Portfolio management is a good technique to identify which programs or projects an organisation should undertake. It is an objective way of allocating resources to identify the best value to be gained from available resources. Used properly it will also involve all business areas within an organisation rather than just the IT Department - increasing buy-in and the sense of value of the project.
However good an individual program or project may look, it may not be the best one to be undertaken by the organisation.
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