Deploying SAP S/4HANA because you are forced to by the end-of-support schedule is certainly the least good reason to migrate. On the contrary, you should take advantage of this generational change to modernise the processes that drive your business, so as to benefit from the technical innovations of this new version. It brings a powerful ‘in-Memory’ database and a host of functions that did not exist in SAP ECC 6. However, migrating a system that has been in production for 15/20 years is no mean feat, explains Alain Rivet, financial consultant, project manager and architect at S4IC :  « Most SAP installations are now over 15 years old. In that time, many companies have undergone multiple transformations: mergers/acquisitions/subsidiary closures, and all this history is reflected in their ERP. Developing a system with such a complex history can be very complicated. A Greenfield approach is therefore an opportunity to get rid of all this obsolete data. » However, starting from scratch can be problematic. For years, companies have been developing specific applications around their ERP. This represents a considerable investment that is difficult, if not impossible, to abandon at the snap of a finger. « The Greenfield approach is not aberrant in itself, but if you have numerous interfaces it can become costly, » underlines Louis Alves, Finance specialist and Product Costing SA expert at S4IC.

For the expert, SAP is undoubtedly the most configurable software in the world: of the 130,000 transactions it integrates, more than 100,000 are intended for parameterisation. A well-executed Greenfield migration will, above all, focus on this configuration. It is only when the necessary functionality cannot be fully covered that it is supplemented with specific developments.

« Experience shows that it is often preferable to opt for a middle way, » says the specialist. This middle way is the hybrid approach (or Data Selective Transition, the official term used by SAP). The basic idea is simple: an SAP system is easy to modify as long as it contains no data. The idea is therefore to separate the parameterisation of the data and to model the ERP according to the company’s needs before reloading the data. This avoids the pitfalls of archiving and converting data during the upgrade, and gives you the freedom to activate new functions or correct things that were not optimally implemented when ECC was installed. Some processes can be kept as they are if they are considered to be performing well or too critical for the company to change. « If the company decides that its purchasing management does not need to change, the migration team will be able to transfer this process to SAP S/4HANA without any impact on users, » explains the expert. Other processes that are considered obsolete can be replaced on the basis of the best practices implemented by SAP. In this way, the company obtains its own installation of SAP S/4HANA with all the functionality it requires. Its data is then loaded into the system. In this way, the new architecture incorporates everything the company wanted to retain from the past and all the improvements it wanted to make. « As the best practices defined by SAP have not been loaded in full, there are far fewer conversions to be made and users will find many of the codes they are used to. »