> For the complete documentation index, see [llms.txt](https://support.vlex.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.vlex.com/vlex-library/vlex-library-home/content-and-document-types/how-to-use-key-number-topics-for-research.md).

# How to Use Key Number Topics for Research

### Summary

Find Canadian case law efficiently by using the **Maritime Law Book (MLB) Key Number System**. This feature allows you to browse a unique classification of legal documents by topic and sub-topic directly within vLex Library.

### Why This is Important

Using Key Number Topics allows for highly targeted research within Canadian case law. Instead of relying on keywords, you can navigate a structured legal taxonomy to find all relevant cases on a specific point of law, ensuring your research is comprehensive.

### How to Use Key Number Topics

1. Select **Browse** from the main menu on the left.
2. Set your jurisdiction to **Canada**.
3. From the list of collections, select **Key number topics**.
4. Click through the topics and sub-topics to explore the complete catalogue and find relevant case law.

{% hint style="info" %}
**Content Availability** Please be aware that the Key Number Topics classification is available for Canadian case law up to the year 2017.
{% endhint %}

### Best Practices & Pro Tips

* **Combine with Alerts:** After browsing to a specific key number topic and viewing the results, you can create an alert to be notified if any new cases are added to that category.

### Related Articles

* [How to Translate Legal Documents in vLex Library](/vlex-library/vlex-library-home/workflows-and-productivity-tools/how-to-translate-legal-documents-in-vlex-library.md)
* [How to Upload and Analyze Your Own Documents](/vlex-library/vlex-library-home/content-and-document-types/how-to-upload-and-analyze-your-own-documents.md)
* [How to Organize Your Research with Folders, Notes, and Highlights](/vlex-library/vlex-library-home/workflows-and-productivity-tools/how-to-organize-your-research-with-folders-notes-and-highlights.md)

**What's Your Next Step?**

| **New to** vLex Library **?**                                                                                                                                                                                   | **Already a** vLex Library **Customer?**                                                                                                                   |
| --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [See how vLex Library can transform your practice. **Request a personalized demo**.](https://vlex.com/book-a-demo?utm_source=website\&utm_medium=organic\&utm_campaign=web_trial_homepage\&campaign_id=4270741) | [If you still have questions or need help with a specific feature, our team is here to assist. **Contact our Support team**.](https://vlex.com/contact-us) |


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://support.vlex.com/vlex-library/vlex-library-home/content-and-document-types/how-to-use-key-number-topics-for-research.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.