MES RFP (Request for Proposal)

A MES RFP (Request for Proposal) is a structured document used to make MES vendors comparable. The goal is not to collect features but to get answers that reveal real project risks: implementation capability, integration competence, operational model, security, and total cost.

The Five Blocks of a MES RFP

1. Implementation

The critical questions here are not about functions but about approach. What is the standard process for pilot and rollout – with concrete milestones and acceptance criteria? Which roles does the vendor provide, and which must the customer supply? What data and processes need to be clean before go-live? And what is configuration versus custom code?

Vendors who cannot answer these questions concretely will still be running workshops 18 months later.

2. Data Connectivity and Integrations

This is where most MES projects fail. Questions should cover: which interfaces are in production – ERP, PLC/SCADA, historian, LIMS, BI – with reference use cases? What is the integration principle, what is standard, what is a special case? How are error scenarios handled: network outage, delays, duplicates, retries, dead-letter queues? "Yes, we can" is not an answer.

3. Operations After Go-Live

Many vendors sell implementation but not operations. What availability is guaranteed? How do updates work – with downtime, rollback, regression testing? What do monitoring and incident management look like? How does disaster recovery work with defined RPO and RTO values?

4. Security

Security is not "we are secure" but concrete controls. Authentication and SSO (SAML/OIDC, MFA), tenant isolation in SaaS, encryption in transit and at rest, logging and auditability, penetration test frequency and disclosure process, and compliance evidence such as ISO 27001 or SOC 2. Combined with NIS2 requirements, this block has become a mandatory part of every RFP.

5. TCO – Total Cost of Ownership

What does it really cost? License model and cost drivers, one-time costs for setup, implementation, and integrations, ongoing costs for subscription, hosting, and updates, internal costs for IT, OT, and production, costs for extensions such as new lines, interfaces, and reports, and exit costs including data export, notice periods, and transition support.

Three Criteria That Separate Vendors

Integration answers are concrete with mapping, error handling, and monitoring – not "we support OPC UA." Operations are well thought through with SLA, update process, and disaster recovery – not "we'll handle that later." TCO is transparent including integrations, environments, and change costs – not "starting at X per month."

Minimum Standard for a MES RFP

Ten to fifteen mandatory questions from the five blocks are sufficient for a comparison with real substance. Add three end-to-end use cases that every vendor must answer as a solution outline including data flow. And a standardized pricing template for implementation, operations, and extension scenarios – so that offers are truly comparable.

FAQ

Who should be involved in a MES RFP? At minimum production management, IT, and OT responsibility where applicable. Quality and maintenance should contribute the use cases. The decision typically sits with the COO or plant manager, but the requirements come from the operational core.

How many vendors should be invited? Three to five is a pragmatic number. Fewer than three provides too little comparison basis; more than five creates evaluation effort that outweighs the benefit. A rough pre-qualification via RFI before the RFP saves time.

What is the difference between an RFI and an RFP? An RFI (Request for Information) is a non-binding preliminary inquiry to assess the market and pre-qualify vendors. The RFP is the binding document with concrete requirements on the basis of which offers are prepared.

How long should a MES RFP process take? From distribution to offer presentation, typically four to six weeks. Giving more time does not produce better answers – just more text. Clear deadlines and a standardized response format keep the process efficient.