ABSTRACT
The work breakdown structure (WBS) acts as a filter focusing on what has to be done even if it is rectified by taking into account environmental factors. Whenever connections, environmental factors, and instability become so relevant and dynamic that they cannot be neglected, nor frozen by a pre-emptive analysis, the WBS can act as a screening and limiting filter for project reality, which might be misleading instead of being a firm guiding light. The concept of hierarchy expressed by the WBS is valuable even for a complex system, inasmuch as it is an expression of a synthesized vision. Planning and controlling are indeed decisive for project success under the assumption that each and every fundamental element of the project is predictable, and that the correct set of key performance indicators is chosen. Few projects started with both specifications and objectives that were clearly defined, planned, and successfully controlled without substantial changes along the way.
