Must, Shall and Should – the use of these words in GMP

I am often asked what the difference between these words mean in the context of GMP, so in this post I try and explain, using European Union Good Manufacturing Practice (EU GMP) as my point of reference.  However, I think that there are occasions within EU GMP where the incorrect terms have been used in error, as we will see.

The legal bit

There the two main parts to EU GMP, firstly the rules and secondly the guidelines.  For human medicines, the rules can be found in Directive 2003 94 EC.  Here the rules (the laws) for manufacturing sites are found.  As this is a legal document, you would expect to see lots of “musts”.  In-fact, there are none.  It is full of “shalls” with the occasional “should”.  The word “shall” does in-fact mean an expectation, so for “shall” we can also read “must”, which is what you would expect in a legal requirement.

The guidelines

Then there are the nine guidance chapters of GMP.  These are guidelines, and therefore should be full of “shoulds”, as “should” opens up the options for an alternative way of achieving the requirements, which is the way GMP is written.  There are lots of “shoulds” in the nine chapters of GMP, with no “shalls” and a few “musts”.

There are “musts” in the GMP chapters, which at first does not appear to be logical, as how can you have a “must” in a guideline?  Well, you can, and this is generally explained when the guideline is repeating the actual requirement of the law (or article of the Directive) itself.  For example, Article 7 of Directive 2003 94 EC covers Personnel.  Here it states “The duties of the managerial and supervisory staff … responsible for implementing and operating Good Manufacturing Practice, shall be defined in Job Descriptions.  Their hierarchical relationships shall be defined in an Organisation Chart”.

So, you need to have Job Descriptions and you need an Organisation Chart.  In the corresponding Chapter 2 of the Guide the GMP (Personnel) we have a “must”, at clause 2.2 which states “The manufacturer must have an Organisation Chart”.  So this makes sense, as there is a “must” as it is repeating the “shall” from the Directive itself.

However, this logic is not repeated with the requirement for Job Descriptions.  You would expect to also see a “must” here too, but in-fact we get a “should” as it states “people in responsible positions should have specific duties recorded in written Job Descriptions”.  So the use of words is not always right and consistent.

This is likely to be due to general errors that have crept in over time and may be due to words being translated from one language to another incorrectly.  So, I do not think that I have answered the actual initial question correctly, other than you should see “musts” and “shalls” in the Directive and “shoulds” in the guidelines, however, as we have seen, this is not always the case.

If you have any comments on this, please let us know.