# Key number topics

The Canadian legal system organises its case law using a number system for different areas of law. You can browse vLex content using the **Maritime Law Book (MLB) Key Number System**; there are over 100 topics and tens of thousands of sub-topics.

Go to **Browse** and set your jurisdiction to Canada. Among the other options, you will see the **Key number topics** menu. Select it to explore the complete catalogue.

![](https://1556743161-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MS8Dq_iqEIflAmbaOkI%2F-MfDVCs6HKrtLyIg82Vg%2F-MfDhMWiY9HoATklTwEc%2FKey%20number%20topics.gif?alt=media\&token=490b64f8-6e98-4ef1-a9b5-22b1cf339420)

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Combine key number topics with alerts and get notified about new case law that falls into any category.
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Key number topics are only available up to 2017.
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