Big bang or phased implementation?

Implementation of planning software: part 2
Big bang or phased implementation?

Timewax explains in a number of blogs on what you should make a decision to implement your planning software successfully. Part 2: Big bang or phased implementation?

It applies here too: you have a small business and you just want to improve the planning process, then you should rather opt for a ‘Big bang’ approach. With multiple departments as well as processes for time recording and invoicing, this way is less obvious.

With a ‘Big bang’ you enter the new planning software for all departments and processes at the same time. This gives the fastest results, but it also comes with the risk of break-downs.

Compare Big bang vs. Phased implementation
Figure 1: compare Big bang vs. Phased implementation

If possible, always opt for a phased implementation. It is always better to book a few smaller successes. I also call it the salami tactics: Do not eat the whole sausage in one go, but slice for slice".

The disadvantage of a phased implementation is that you end up with temporary links. This is because department A already works in the new planning software and department B still works with old software. If you work in phases, it is important to look for the salami slices that are least dependent on each other.

  • Roughly, you can break up the project in two ways:
  • 1.  Functional
  • 2.  Organizational


With a functional approach, you can for example choose to first implement the planning module. Planning and the systems used for this purpose (often Excel!) are rather separate parts within an organization. This can be separated pretty easily without too much impact.

Once you start planning, it will be much easier to get people to do time recording based on the planned hours in the system. You basically already have all the planned hours as a starting point from the planning module. For employees it then becomes a simple matter of copying hours and make adjustments where necessary.

The invoicing is also often done in separate systems, like in an accounting system. The invoicing module can be implemented last, at a time when everything is running smoothly. That is an important condition, especially in projects where you invoice based on time material.


With an organizational approach, you implement the software per department: first all modules of department A, then of department B, and so on.

You can also decide to first introduce the planning module for department A and then for department B. You'll basically get a mix between an organizational and functional approach.

What you should in any case consider well in deciding whether an organizational phase is possible, is the extent to which departments work together to a high degree (or operate autonomously from each other). See the chapter on the business factors in our first blog about implementation. With a high level of cooperation it is often not possible to implement a module by department. You then create a situation where one department works on system A and the other department on system B, while the systems have to communicate with each other. This increases the complexity and provides extra work.

Mark de Jong
Mark is Sales & Marketing Manager at Timewax. He has a background as a project and resource manager with PricewaterhouseCoopers Management Consultants with expertise in the field of Professional Service Automation (PSA)