When is a glossary appropriate?

Here's another correspondent from the SMART group, we'll call her Smart-L

I read that a key requirement is that vocabulary should be known / understood by team members and other stakeholders, and it occured to me that perhaps it would be an idea to include a 'project glossary' in the plan, to ensure anyone reading it would understand it correctly - would an appendix, or perhaps some other area of content such as the 'Stakeholder Management Plan' be appropriate?

If we take the previous remarks about common knowledge on board, then it should be assumed that all readers would know basic PM terminology, such as "WBS" or "critical path" fairly well. You might consider including a glossary if the project possessed lots of odd technical terms, or if your project methodology used specific terms (I'm thinking of PRINCE2's use of words like Supervisory Board). Then it's good to include such a glossary if needed.

Don't be afraid to mix up the recommended structure a little, if you think the project needs it.