Core HR project: 6 lessons from the field, shared by a DSI

1. Start from real uses, not a list of features.
2. Define roles clearly, from the HR department to the integrator.
3. Treat data quality as a workstream in its own right.
4. Anticipate interfaces, even in an SAP environment.
5. Prepare for life after the project from the scoping stage.
6. Secure business team availability at the right time.

Key figure:

According to Strada’s global report published in July 2025, more than half of French companies still use two or three separate HR systems. This fragmentation makes HR data harder to manage.

Because the quality of a Core HR system is judged by what it enables people to do day to day, not by the number of features switched on. Starting from real uses avoids building a tool that looks complete on paper but is cumbersome to use. The risk is real: poorly gathered requirements can derail an HR system project.

In the field: Maïsadour set a clear principle from the outset: make Employee Central the system of record for employee data, with payroll fed by this module. The team stuck to it, even when tempted to add ever more detail.

In practice:

• Express each requirement as a use case: who does what, and why?
• Set a simple guiding principle that everyone shares.
• Keep requests for extra detail for a later phase.

The pitfall to avoid: writing the specifications as a feature catalogue.

The question to ask: what concrete use does each piece of data we manage serve?

Each player must keep to their role from scoping to go-live. When roles become blurred, decisions stall and the project drifts.

In the field: At Maïsadour, responsibilities were clearly divided:

• The HR department owns the requirements. It is not for IT to express them on its behalf.
• The DSI ensures consistency with the existing information system.
• The integrator brings expertise on the solution, a genuine advisory role and frankness about what the tool should not be asked to do.

The pitfall to avoid: a DSI that defines requirements on HR’s behalf, or an integrator that says yes to everything.

The question to ask: who decides what, and who has the final say if there is disagreement?

Because a Core HR system is only as good as the reliability of the data it holds. If migrated data is incomplete or inconsistent, users quickly lose confidence in the tool.

Industry professionals agree: according to the Shortways 2024 barometer, 78% of HR and HRIS professionals surveyed believe data quality deteriorates when an HR system is poorly adopted.

In the field: Internationally, Maïsadour’s data was scattered across several tools. It had to be gathered and cleansed, working with many local contacts.

In practice:

• Appoint an owner for each type of data, in each entity.
• Start data migration early, alongside the design phase.
• Allow time for back-and-forth with local teams.

Good to know: the system of record

A master HR system is the central reference system that gathers and organises a company’s core employee data. Other applications receive this data but do not change it. Having a single system of record for each piece of data avoids duplicates and inconsistencies.

The pitfall to avoid: treating data migration as a technical task at the end of the project.

The question to ask: who is responsible for each piece of data, and in which entity?

Because a Core HR system never works in isolation. It exchanges data with payroll, the ERP, recruitment tools and time management tools. Every exchange is a potential point of weakness.

In the field: Maïsadour connected Employee Central to its SAP HCM payroll through SAP Integration Suite. The project was also an opportunity to change integration tools. The lesson learnt: even between solutions from the same vendor, interfaces do not simply plug in.

In practice:

• Map all data flows from the scoping stage.
• Check that integration skills are available, in-house or with your partner.
• Plan end-to-end testing with real-life cases.

The pitfall to avoid: assuming that solutions from the same vendor communicate effortlessly.

The question to ask: do we have the integration skills we need, and for how long?

From the scoping stage. For Nicolas Tasseel, an application’s life does not end at go-live: it creates value when it works day to day, with its users.

In the field: Maïsadour organised knowledge transfer to its internal administrators. Right-sized TMA from Arago covers one-off questions and peaks in activity.

In practice:

• Document design choices as the project progresses, not at the end.
• Identify process owners and key users.
• Train your administrators so they can add a field, a rule, a country or a company.
• Size support according to your real needs.

The pitfall to avoid: discovering after go-live that nobody in-house has mastered the solution.

The question to ask: who will run the solution day to day, and with what documentation?

By planning for it as a scarce resource. HR teams still have to run day-to-day operations during the project: without their availability at the right time, nothing moves forward.

In the field: Maïsadour’s HR teams also had regulatory deadlines and HR campaigns to manage. Their availability was managed day to day, in close contact with managers. Go-live took place in three stages, aligned with HR cycles: central HR, managers, then all employees.

In practice:

• Cross-check the project plan against the HR calendar from the scoping stage.
• Book business experts for key moments: design, testing, training.
• Open the system in stages, starting with the users closest to the project.

The pitfall to avoid: building a project plan that ignores HR activity peaks.

The question to ask: when will our HR teams really be available?

What about the standard?

“Demanding on the standard, pragmatic about everything else.” Nicolas Tasseel, Solutions Director, Maïsadour

Staying close to the SAP standard makes maintenance and upgrades easier. When a need is not covered, there are several options: configuration, proven models, bespoke development or an SAP-certified application. At Maïsadour, the drafting of employment contracts was handled by Arago Document Manager.