Writing Procedures; Must, shall, would or could

Man writing on a clipboard

When people write procedures, there often is little consistency in the words they use to form the tense, mood or voice of their sentences. Let me explain…

  • The report is to be reviewed before it is sent to the client.
  • The report may be reviewed before it is sent to the client.
  • The report must be reviewed before it is sent to the client.
  • The report shall be reviewed before it is sent to the client.
  • The report should be reviewed before it is sent to the client.
  • The report will be reviewed before it is sent to the client.
  • The report can be reviewed before it is sent to the client.
  • The report might be reviewed before it is sent to the client.
  • The report could be reviewed before it is sent to the client.

As you can see by reading each of the sentences above, just changing one word can infer quite a different meaning.

The words we are talking about here are called ‘auxiliary verbs’ (often called helping verbs), and there are both primary and modal auxiliary verbs. Primary auxiliary verbs are: be, do and have. However I want to focus on modal auxiliary verbs such as: can, could, may, might, must, shall, should, will and would.

So which ones should you use? Well it depends on what you’re trying to say. For example: is to, must, shall and will all mean that something needs to happen. Whereas the words: may, should, can, might and could, all imply some form of recommendation or guideline – where the user makes their own judgement as to whether to follow the recommendation/guideline or not.

So what is the point of all this, and what words “should” be used?

Modern legislation here in Australia tends to use the word “must” – meaning you have to do something because if you don’t, you’re breaking the law. Must is a very strong word. For more clarity on this, the internet provided this useful explanation from the USA Federal Aviation Authority…

We call “must” and “must not” words of obligation. “Must” is the only word that imposes a legal obligation on your readers to tell them something is mandatory. Also, “must not” are the only words you can use to say something is prohibited. Who says so and why?

Nearly every jurisdiction has held that the word “shall” is confusing because it can also mean “may, will or must.” Legal reference books like the Federal Rules of Civil Procedure no longer use the word “shall.” Even the Supreme Court ruled that when the word “shall” appears in statutes, it means “may.”


So even though the word “shall” is still found in legislation, it is tending to be phased out.

Interestingly, “shall” is the word that is used by the International Organization for Standardization (ISO) and other National Standards bodies such as Standards Australia. The logic behind this useage is that even though the requirements within a standard are mandatory, the standards themselves are voluntary. So you only have to do something if you adopt the standard. Confused?

You may therefore think that “shall” is a good word to use in your procedures; but the problem with “shall” is that it is a word that is dying in use. In fact, this chart available in google shows the number of times “shall” has been used in books over time, peaking at around 0.105% in 1820, falling to 0.019% in about 2000. We believe the little rise after 2000 could be due to the increase in the number of standards that are being written.

Use over time for: shall


Basically “shall” is a word that is no longer used in normal conversation. We don’t generally say things like: “We shall check the fuel before we go on a trip.” It’s more likely that we say: “We must check the fuel before we go on a trip” or “We will check the fuel before we go on a trip”. So “shall” in normal speak is often replaced nowadays with “must’ or “will”.

So what would/should you use when you’re writing documents for your management system?Firstly, if it is a mandatory activity that has to be done, then “must” is probably the best term to use. The same applies for “must not” if something really is not allowed. For example:

The supervisor must review and approve the entry permit before work commences.
This door must not be propped open.

If there are options for the activity, then “could” is useful; for example:

The views of interested parties must be established, and these interested parties could include;

  • government
  • clients
  • local communities
  • suppliers
  • members of staff.

“Could” is also used to express possibility; for example:

  • In an extreme weather event, the river could flood.

Finally let’s have a look at these words: should, will and may.

“Should” is normally used to make a recommendation or to give advice; for example:

  • The work should start before 7am.
  • Other people should be quiet when the trainer is presenting.

“Will” is used for promises or voluntary actions that take in the future; for example:

  • The purchasing officer will buy the goods.
  • The most efficient method will be to use two competent people.

“May” is for when something is possible such as:

  • The worker may get injured if the ladder is used.
  • The report may not get read if it is too long.

This short article is not meant to make you an expert wordsmith, but hopefully it will help you be clearer when you write, edit or review a policy, process or procedure.

…and please, please don’t fill every sentence up with the word “shall”.




great article, I am now conflicted as I utilize ISO standards extensively.


Thanks, this article was really useful, I will share it with my classmates.


Thanks. I’m forever striking out shall from draft procedures and approval documents and I feel better about it now.
Next on the list should be “…including, but not limited to:”

Leave a Reply

Your email address will not be published.

“Well structured content, fantastic presentation by Miguel and loads learnt. The ISO 27001 training is helping me understand my clients’ needs better and make useful recommendations. Moreover, this was so much fun – thanks team!”

“Overall very valuable course. Balance of theory with practical workshops was excellent. Trainers stuck to timetable very well.”

To be honest, I wasn’t really looking forward to the training and wasn’t too sure what to expect. It turned out to be quite enjoyable and a really great experience which I put down to the facilitators, Pat and Tom and the group. Both Pat and Tom shared their breadth of knowledge and experiences and were really engaging.

“Great presentation of the course, engaging facilitators and good use of group work. I found the course to be a great refresher for an audit course I did 10 years ago and now feel more motivated to go audits in a non-bow tie way!”

“Trainers’ knowledge was excellent, their knowledge made the training and learning easy.”