A fundamental part of project plan is related to the strategy to deploy/implement, there are multiple patterns but essentially these can be summarized into four main strategies commonly used to introduce system changes:-
a) – direct changeover.
b) – parallel changeover.
c) – pilots.
d) – phased.
Of course decision on the implementation strategy are connected to the nature of the project where a bridge is different than a new ERP system
a). Direct changeover
Called the big bang – On day one of implementation the old system ceases and the new one get live. This approach is in many ways simpler, has the advantage that it is more definite and clear cut, and if it works there will be less disruption. However it can be more risky, and if it doesn’t immediately work well can lead to chaos. If this approach is used then it is wise to do as much prior testing as possible.
b). Parallel Changeover
Running of the new and the old in parallel until the new system is operating without problems.
This has the advantage that one can be sure that the new system is working well before the old one is discontinued. However, running two systems usually takes more resources and can lead to confusion. It does ensure continuity of output but often with loss of productivity.
c). Use of pilot projects in part of the organisation
Introduction of the change for a trial period followed by a review.
This has the advantage of testing out the changes in a contained area and has proven often very useful in identifying unexpected problems and side-effects, and testing not just the changes but the way they should be best introduced. Can be used together with all the other approaches. Needs careful choice of pilots.
d). Phased Introduction
These approaches are highly suitable for large scale changes and for changes in geographically dispersed organisations. They both make large changes more manageable.
Introducing the change into the whole organisation one bit of change after another.
The changes can be introduced in small steps with training being done in stages. Not all changes can be broken down in this way and even if they can, it can be a lengthy process.
Introducing the whole change into parts of the organisation.
Here one can test and trial the ideas in some areas, possibly those most ready for change, and then into other areas – “learning-as-you-go” and building on successes. Thus a fairly safe approach but again it can be quite a lengthy process.
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