# 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)

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