Functional iterative software implementation: module by module to success

To successfully implement complex enterprise software, it is important to choose the right strategy. In the functional iterative approach, the individual functional modules of the new software are introduced into the company one after the other. Of course, this assumes that the software is a modular product consisting of individual functional modules that are functional and ready for use on their own. The approach can therefore also be described as a module-by-module iterative implementation.

All users start using the new software module at the same time and across departments. The introduction of the next module takes place only after:

• the use of the module has been fully adapted and accepted,
• problems have been identified and solved
• all necessary interfaces have been implemented.

This approach buys the developers time to develop the interfaces of the modules one by one. If the company wants to replace various software products with one overall solution, the functional iterative implementation is a good choice.

In the preparatory phase of the software introduction project according to the functional iterative approach, it is essential for project managers to pay attention to the functional dependency of the modules on each other. From this dependence a meaningful introduction sequence is to be derived. According to this implementation sequence, in turn, the work breakdown structure must be designed accordingly.

Before the introduction of each individual module, employees should be trained in its use and it must be determined to what extent the legacy system is to remain connected. This must be taken into account in the project planning for the entire implementation project.

In the case of closely coupled functional modules that are highly interdependent, simultaneous implementation makes sense. Such a simultaneous introduction of two modules is advisable, for example, in the case of the function modules for quotation generation and project-specific document management, as this is the only way to send quotations with accompanying documentation. In the context of project management software, however, function modules such as time recording and project planning should not be introduced as the first modules at the same time, as this significantly increases the complexity of the introduction and can quickly lead to problems.

The selection of the module for the first iteration has a signal effect on user acceptance and should therefore be well considered and its introduction well prepared. Once the workforce has gained a positive view of the software introduction, this greatly simplifies the subsequent introduction phases. A functional module that can be easily used by all employees and whose benefits are quickly apparent to every user is a good choice here, for example a digital system for recording working hours and vacation management.

If a company has several sites, a functionally iterative implementation can sometimes be very complex and time-consuming, especially if the different sites also use different software products that need to be replaced. This places high demands on the project management of the implementation project. If only a single function module is to be implemented, the functional iterative strategy is not applicable. A regionally iterative approach or a project-oriented rollout would be preferable here.

Your framework conditions are not optimal for the application of functional iterative software implementation? Numerous other options are open to you:

The functional iterative approach is a rollout strategy for modular enterprise software in which the individual functional modules are introduced into a company one after the other. In the process, dependencies must be taken into account and the implementation sequence as well as the work breakdown structure must be adapted. Employees must be trained before the modules are introduced and it must be determined how the legacy system is to remain connected.

The strength of this variant is that the interfaces of the modules are developed one after the other and problems can be solved before the next module is introduced. This implementation strategy is recommended if a process is to be carried out in the same way throughout the entire company.