Manage by sub-category or tag?

Hi Team,

I’m recently new to being an admin for discourse, however I have been a user in many places for some time. I’d like help with working out how best to manage categories/tags please.

I have categories Industrial, Commercial and Domestic. Under Industrial I have sub-cat Oil and Gas, Mining and Power Generation. I’d like a third tier which I thought I could manage with tags. The trouble is, when I make a tag compulsory, for example under Oil and Gas I have Onshore and Offshore, I then can’t appear to have additional tags that the users can create. If I add another tag group, say cable, wire, EEHA, motor, then these can be used as the compulsory flag too…which goes against what I would like.

This is an example of a preferable hierarchy. (Example could be onshore be a compulsory tag and any-tag be any tag, or any tag group.

└─   Oil and Gas
│    └───Onshore
│    │   -   any_tag
│    │
│    └───Offshore
│        -   any_tag
└─   Mining   
│    └───Extraction
│    │   -   any_tag
│    │
│    └───Processing
│    │   -   any_tag
│    │
│    └───Refining
│        -   any_tag
└─   Power Generation
└─   Foo
└─   Blah

Question 1: Have I missed something with how tags are managed?
Question 2: If not able to specify a compulsory tag from one group, and then any tag after, am I better off making the Sub-categories Oil and Gas - Onshore, Oil and Gas - Onshore?

Thanks for your time in helping me better understand the workings of these. For the record, I have searched in past questions but they only seem to cover mandatory groups or free tags, not a mixture of both.


This is not super trivial, so don’t feel bad about having to seek help. I’ve done a lot with tags and I still had to do some trial and error. Here’s what I think you are looking for. If I’ve misunderstood, just let me know.

  1. Create a Tag Group (found at /tag_groups) called “Oil and Gas” with the following settings

  2. Go to the Oil and Gas sub-category and open the category settings to the “Tags” tab and configure like so:

  3. Users will now receive a message if they try to submit a new topic without an Oil and Gas tag:

    And they will be able to add/create additional tags according to how you’ve configured your site settings:

As an aside, there is a third level of sub-category you can enable from the console as an alternative, but the tag approach is a really solid approach and more performant if you are expecting to have quite a few categories on your site.


Please, can you explain how I can do this? Thank you.

1 Like

Sure, take a look at the following post:

I would also encourage you to read through It’s Time We Talked About Tags. Deciding how to organize your forum is tricky and that blog post provides a great breakdown of the different benefits of categories and tags.


Oh my. I’ve been longing for this ability for years on my forum. Can’t believe it’s been there for a while now and I didn’t realise!