GMP · Foundations

What is GMP?

Good Manufacturing Practice (GMP) is the body of rules that requires medicinal products to be consistently produced and controlled to the standards appropriate to their intended use — so that quality is designed and verified in, not tested in afterwards.

In one line

Good Manufacturing Practice (GMP) is the body of rules that requires medicinal products to be consistently produced and controlled to the standards appropriate to their intended use — so that quality is designed and verified in, not tested in afterwards.

Plain-English explanation, then the primary regulation it comes from.

Explanation

Understanding what is gmp?

The premise behind GMP is that you cannot test quality into a product. A finished-product test examines a sample, not the batch, and it can only detect the failures somebody thought to look for. If a batch was made under uncontrolled conditions, a passing result tells you the sample passed — nothing more. GMP exists because the only reliable way to know a batch is fit for a patient is to control how it was made.

That leads to the two obligations underneath everything else: do what you wrote down, and be able to prove it. Every significant activity has a defined procedure, and every execution of that procedure leaves a record. An inspector who cannot reconcile what your procedures say with what your records show has found the gap the whole system is designed to close.

GMP is not optional guidance. In the EU a manufacturing or importation authorisation is conditional on compliance, and an inspectorate can suspend it. The commercial reality is blunter still: a GMP non-compliance statement published on EudraGMDP is visible to every customer and partner you have.

GMP is also deliberately non-prescriptive in places. It rarely tells you exactly how to do something — it tells you what outcome you must achieve and expects you to justify your approach. That flexibility is why two compliant sites can look quite different, and why 'we have always done it this way' is not, on its own, a defence.

What it requiresThe substance of the requirement, stated plainly.
Quality is built in, not tested in
Controls sit in the process, not only at the end of it. Finished-product testing confirms the process worked; it cannot rescue a process that did not.
Say what you do, do what you say, prove it
Procedures define the activity, records evidence it. The distance between the two is the single most common source of findings.
It is a licence condition
Manufacturing and importation authorisations depend on continued GMP compliance, verified by periodic inspection.
Scope is wider than the production floor
Premises, equipment, personnel and training, documentation, quality control, outsourced activities, complaints and recalls, and self-inspection all sit inside GMP.
Outcome-based, not recipe-based
Most requirements state what must be achieved. You choose the method and carry the burden of justifying it.
Where it goes wrongThe part a definition alone will not tell you.

Common failure modes

  • Procedures that describe an idealised site rather than the one that exists, so the real process quietly diverges and the records show it.
  • Treating GMP as the QA department's responsibility, when the obligations land on production, engineering and management as much as on quality.
  • Documenting a control that nobody performs — worse than having no control, because it evidences your own non-compliance.
  • Assuming a passing release test closes out a process that ran outside its validated parameters.
Primary sourcesAlways verify against the primary source before acting; guidance is revised.

Where this is written down

Related

Read next

Looking for a definition rather than an explanation? The GMP glossary covers the abbreviations in one line each.

Applying this to your site

Knowing the requirement is not the same as closing the gap

If you want to know where your site actually stands against this, the readiness score covers seven quality-system domains in twenty questions, and takes about ten minutes.