In the next five years, SAP customers have a big decision to make. SAP will stop supporting ECC 6, a widely-used version of the company’s ERP software, which means customers need to think about making the jump to SAP S/4HANA.

But that’s easier said than done. Migrating all your data and operations—from finance to supply chain to human resources—to a new version of the SAP platform is a complicated process.

It’s a move, however, every SAP customer is going to have to make, as long as they want to keep using the supported version of ubiquitous ERP software. Fortunately, there are a few options for companies looking to implement SAP S/4HANA. Depending on a few important factors such as the size and state of your data, your company’s use of SAP, and any future business needs, there are three main methods to roll out the new version: greenfield, brownfield, and a hybrid of the two approaches. Choosing between these three implementation strategies can be tricky, and depend on a few factors. We’ll parse the differences between these approaches, and help you figure out which approach fits your needs best.

What Is a Greenfield Deployment for SAP S/4HANA?

Like wiping a slate clean, a greenfield approach is essentially a reset button. A transition using a greenfield approach is a complete reengineering of a business’ SAP processes and workflows. Additionally, any customization done on SAP ECC 6 is completely wiped away during a greenfield implementation. This certainly has its pros and cons. For a legacy organization that has been using SAP for a long time and has accumulated a lot of complicated workflows and heavily customized code, a greenfield approach might be the fresh start needed to overhaul its use of SAP and reduce complexities. This is what the “back to standard” movement among SAP customers is all about. Greenfield is also perfect for companies new to SAP, if they are moving their data over from a non-SAP system.

It’s worth noting that a greenfield implementation is what SAP recommends when making the jump to SAP S/4HANA. It can be done either on-premise or in the cloud, and allows users to predefine migration objects. From a cost standpoint, greenfield implementations result in lower total-cost-of-ownership (TCO) and time-to-value.

Theoretically, you can have the core elements of SAP S/4HANA up and working in about three months. But, migrating all your data onto a blank system can take some time. This is a significant undertaking and will almost certainly take longer than three months. What’s more, it’s definitely a riskier maneuver than a different implementation strategy. You also need to redevelop any necessary system customizations critical to your business that you were previously running on another version of SAP, which can be another significant time sink.

What Is a Brownfield Deployment for SAP S/4HANA?

Whereas greenfield is a complete overhaul, a brownfield approach is more like an upgrade or renovation of your SAP ERP. You can get SAP S/4HANA up and running, while also migrating your existing SAP workflows and systems over to the newest version of SAP. You also can keep your tried-and-true business processes, along with the customizations you’ve been using to manage your data. Yet, you don’t have to bring everything over. Brownfield lets users reevaluate and edit their existing processes, and port over the ones that are working. On paper, a brownfield approach is both the cheapest and fastest implementation strategy. It’s also a lot less risky than greenfield.

Yet, brownfield isn’t without its downfalls. Since you are essentially porting over everything from your previous SAP operating system, it’s often seen as an innovation block. The success of the implementation lives and dies by how well your current workflows and systems are replicated. This doesn’t give a lot of room for examining how to cut through the complexities and poor workflows of your current process. Because of all the complexities that come with porting over customization and workflows, a brownfield implementation is best done on-premise.

Brownfield is best for customers who are looking to continue using their current solutions and rapidly convert from SAP ECC 6 (or another version of SAP) to SAP S/4HANA.

What Is a Hybrid Deployment on SAP S/4HANA?

The hybrid implementation is probably the most widely used model. At the end of the day, large businesses need to redesign some of their workflows and systems, while also maintaining some critical customizations and solutions. Simply starting over from scratch or transferring your data and workflows over to a new version of SAP is going to cost both time and money. A hybrid approach—which cherry-picks the best parts of greenfield and brownfield implementations—is best for large companies with a lot of data and complex systems. There are a lot of hybrid approaches to choose from that pull different aspects of greenfield and brownfield implementations.

With a hybrid approach, you mitigate a lot of the risks associated with making the jump to SAP S/4HANA. You can selectively redesign certain aspects of your system, while also keeping the ones that work at the same time that you’re cleansing and moving your data into the new system. The only real downside is that a lot of hybrid implementations require a third-party solution or tool to get the job done and distill the aspects of greenfield and brownfield that are part of the migration plan.

Choosing which SAP S/4HANA implementation strategy is right for your company can be a difficult process. A lot hinges on your successful move over to the newest version of SAP. If you decide that a move would benefit your organization, the good news is that there are options for a successful journey to SAP S/4HANA.

Want to continue the SAP S/4HANA conversation? Make sure to attend the ASUG Best Practices: SAP S/4HANA Virtual Experience. Across four weeks in March, these sessions will help attendees be successful in every part of their SAP S/4HANA journey, with each week focusing on a different phase of the implementation process.