What is meant by a complex project?

The world if full difference when we talk about complex projects. Is complexity the same as complicated? By complex do we just mean a large project, one which is geographical distributed or using complex technology? Or are these mega project just more complicated.

Complexity

Within business complexity is defined as

“Complexity describes the variances in approach and their consequences on the business”

I think complexity is closely related to ambiguity of project goal and method of delivery, because complexity is caused by the challenges of planning the project in the first place and likely level of anticipated change. This complexity makes it impossible to sit down and plan the project in a clear way from start to end; we need a slightly more flexible approach to the traditional “plan the work” “work the plan”. This can be represented by an adaptation of Rodney Turners classic goal method matrix

The higher the levels of ambiguity about the project goal and uncertainty about the delivery method make it more difficult to manage in a traditional way. This seems more important than the pure size of the project. Some large complicated projects have clear goals and known methods and these can be managed in a very traditional way. This definition differs from the normal multi organisation; multi-phase definition defined by the APM, but is nevertheless more relevant to help think about the complexity of the projects we manage.

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