What is GEMMA?
GEMMA stands for Gemeentelijke Modelarchitectuur (Municipal Model Architecture) and is the reference architecture for Dutch municipalities. GEMMA helps municipalities to structure, manage and improve their information provision in a way that aligns with national frameworks such as NORA.
GEMMA translates the general principles of NORA into municipal practice: concrete, actionable and reusable.
🧠 Purpose of GEMMA
| Objective | Explanation |
|---|---|
| Coherence and structure | Ensures alignment between processes, applications and data |
| Reuse of standards | Promotes interoperability and vendor independence |
| Local realisation of national frameworks | Aligns with legislation and central government architectures such as NORA |
| Accelerating digitalisation | Supports municipalities in transforming to digital service delivery |
🧱 Structure of GEMMA
GEMMA consists of multiple layers and components:
| Architecture layer | Description |
|---|---|
| GEMMA Processes | Standard business processes for municipal tasks (Cases, Taxes, etc.) |
| GEMMA Data | Information models such as RGBZ (case-oriented), BAG, BRP |
| GEMMA Applications | Classification of applications and their functions |
| GEMMA Infrastructure | Underlying technical facilities: networks, workstations, cloud, etc. |
Each component is reusable and linked to national standards such as ZTC, Digikoppeling, eIDAS, etc.
🔗 Relation to other architectures
| Architecture | Relation |
|---|---|
| NORA | GEMMA is the municipal elaboration of NORA |
| WILMA | Water authority variant, in line with NORA but with sector-specific accents |
| PETRA | Provincial elaboration of the Dutch Government Reference Architecture |
| MARIJ | Central government variant, aimed at ministries and executive agencies |
🏙 GEMMA and the physical living environment (OT integration)
Although GEMMA is primarily focused on information systems (IT), there is growing demand for integration with Operational Technology (OT), such as:
| Application | Example |
|---|---|
| Smart public spaces | Lighting, traffic lights, sensors connected to municipal networks |
| Water management | Linking municipal IT with pumping stations/measurement points (OT) |
| Environmental zones and parking enforcement | Real-time street-level sensor data combined with back-office IT |
| Municipal data platforms | Integration of IoT data within GEMMA information models |
Because of these developments, alignment between GEMMA and OT architecture is becoming ever more important for municipalities.
📌 In summary
GEMMA provides municipalities with a practical and coherent framework for structuring digital service delivery and data exchange. It bridges national architectural principles (NORA) and operational practice — including where OT and IT meet in public spaces.