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Developing a subject-based taxonomy for GOV.UK

Posted by: and , Posted on: - Categories: Finding things, Product changes

Why is the topic taxonomy important?

We want users to be able to find related content across government about a particular topic via a single browse structure. This is central to  the vision for improving navigation on GOV.UK, as Ben described in this recent blog post. Because content on GOV.UK covers so many different subject areas, and is for so many different audiences, we need to make sure it’s organised well.

To support this we’ll need publishers across government to classify all the content on the site by subject, using a single list of subject terms.

This emphasis on a single unified list represents a shift in our thinking over time. Previously we’d assumed that we needed separate taxonomies for different groups of users and different types of content (mainstream/specialist/policy). We now think a single taxonomy which includes all content and meets the needs of all users will make it easier for users to get to the content they need, and for publishers to classify their content.

We’re calling this single list of subjects the topic taxonomy. By 'topic' we mean a word or phrase which generally describes what a piece of content is about (not what type of content it is or who it’s written for). By 'taxonomy' we mean a hierarchical classification system with broader terms at the top and narrower terms beneath (and probably also including some relationships between related terms).

We already have the beginnings of a pan-government topic taxonomy on GOV.UK but, for the reasons described in a previous blog post, it’s patchy and inflexible. We’ve been continuing to develop our ideas about how to expand and complete this taxonomy over time to cover all GOV.UK content.

The topic taxonomy should:

  • use terms that reflect users’ language and mental models
  • bring together content published by multiple organisations across government in useful ways, so users can see all related content regardless of who published it
  • eventually be comprehensive enough to include all the different subject areas covered by the GOV.UK site
  • be the only subject-based classification system used on the site

This topic taxonomy will provide the foundation for supporting the improvements to navigation, search and orientation described in the vision.

How are we developing this taxonomy?

Our planned approach is to develop terms in the taxonomy by looking at content and user needs theme-by-theme. These themes are high-level categories like education, transport and environment. We want to join up content within themes, and eventually across themes too.

To end up with a single taxonomy (the list of subject terms) we’ll need to merge policy subjects, mainstream browse categories and topics into one classification system as we work through each theme. This merging process will be essential for pulling everything together for users so it can be found in one place.

To develop the terms in the taxonomy we want to work with groups of organisations relating to each theme so that we can involve subject experts. We also think it’s important to consider content strategy alongside the taxonomy. Most importantly we want to include as much user research as possible.

However, we know the taxonomy is never going to be perfect, and is a living thing that will inevitably change over time. It’s always going to need tweaking.

The taxonomy is a framework

Creating the taxonomy is one key step in the process of making it easier to find things on GOV.UK. It provides a framework for organising content on the site.

For the taxonomy to be successful in helping to solve the 'finding things problem', content must be tagged to topics in an accurate and consistent way. Therefore, we know we must also make the tagging process for publishers as simple as possible. We have some ideas about this, which we’re currently testing and will blog more about soon.

The taxonomy isn’t the same thing as navigation

Although we envisage all content on GOV.UK being tagged to one or more topics, the topic taxonomy is not the same thing as site navigation. The taxonomy will drive and underpin the navigation and will help users better understand how the content on the site is organised and how everything fits together. For example, it will help to orientate users in the site structure by supporting consistent breadcrumb trails on content pages.

However, the ways in which the taxonomy can be surfaced in the site design to support navigation (ie how the information is presented and how users interact with it) is a related but different strand of work. We have some ideas about the ways in which the content tagged to topics could be displayed on the site as users navigate their way through it. The next step is to test and iterate these assumptions.

A good taxonomy allows users to find what they’re looking for without having to give it too much thought. It’s an essential part of the site that lives beneath the surface and defines its foundations.

What’s next

In the next couple of weeks we’re starting work on building out and improving the taxonomy for all the education content on GOV.UK - our first theme. We’ll be blogging about this process as we go along.

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  1. Comment by Adrian Barker posted on

    I presume you're aware of all the work done on taxonomies, controlled vocabularies etc. in the past? (Not wanting to suggest you don't know how to suck eggs - I don't!). One done within local government (but covering other subject areas too) is:, though it doesn't look as though it is being updated any more.

    I've been testing using it for a weekly policy update I do and it is quite useful but misses out a number of topics where it would be useful to have an entry (e.g. antimicrobial resistance, though to be fair, that mainly came to prominence after the list was drawn up).

    It would certainly be useful to have a single, common list that all providers and referencers of information could use.

    • Replies to Adrian Barker>

      Comment by Vicky Buser posted on

      Hi Adrian,

      We're definitely looking at a variety of existing vocabularies as part of this work to see what we can learn from them.

      Thanks, Vicky

  2. Comment by Adrian Cooke posted on

    Do you expect that browse categories will become a subset of the topic taxonomy? Is that what you mean by merge?

    • Replies to Adrian Cooke>

      Comment by Vicky Buser posted on

      Hi Adrian,

      By ‘merge’ we mean that instead of having 3 separate (but overlapping) subject-based taxonomies for browse, our aim is to eventually combine them into a single taxonomy that covers all content on the site. And yes, on the front-end browse categories may end up being a subset of the topic taxonomy - it may not be useful to display all levels of the taxonomy for category browse. We don't know the answer to this yet - it's something we’ll be researching with users.


      • Replies to Vicky Buser>

        Comment by Adrian Cooke posted on

        Makes sense Vicky, thanks for the extra detail.

  3. Comment by Mary Anne Jackson posted on

    I like your approach to this undertaking. As well as working in concert with SMEs do you also employ librarians, especially an experienced taxonomist, or other trained staff such as library technicians to help rationalize all of the contributed terminology? Did you provide any guidelines for the SMEs who participate in a tagathon day?