2 May 2025

You can now give all your Microsoft 365 files a sensitivity label. This allows you to protect your files that contain sensitive data. 
The labels work like a tag, to indicate sensitive, confidential content. This allows you to protect your files that contain sensitive data. Below, you can learn why labelling is important, which labels you can add, and how to do so. 

Why is a label necessary?

• To protect sensitive data: labels can help to protect sensitive information, address details, banking information, passwords and IP addresses.  A sensitivity label informs you – as user or as recipient of a file – how the data should minimally be protected and how to deal with the data. The use of sensitivity labels contributes to the observance of privacy rules and regulations and to compliance with our own security standards for information protection standards. 
• Efficient file classification: good use of labels ensures efficiency. Labels allow you to easily apply the correct security to a file without needing complicated settings. By applying the appropriate labels, it is possible to determine at a glance who should have access to which information and which actions can be taken with the data. This reduces the risk of mistakes and thus also the risk of data breaches. 
• Towards a secure use of AI: last but not least, labelling data is a requirement for introducing a secure AI tool in future, within Leiden University. Without clearly labelled data, it is not possible to use AI tools securely and responsibly within the university. Senisitivity labels ensure that AI knows how to deal with the differerent kinds of data. Without these labels, the risk to the university is that sensitive information is inadvertently used or shared, which is a danger to security and privacy. Data labelling ensures that within the university  we are well-prepared for the secure use of AI in the data and documents that we work with. 

Which sensitivity labels are there?

The four types of label are: Public, Internal, Confidential and Secret.    

Public	Internal	Confidential	Secret
Information can in principle be shared and is available without restrictions.	Information is available for all or defined groups of staff, students, researchers and guests of Leiden University and may freely be shared.	Information is available for a specified group of authorised staff of Leiden University and staff of authorised third parties that require access for the performance of their duties.	Information is only available for specific, named individuals (internal as well as external, depending on need and necessity).

How to apply a label?

If you wish to add a sensitivity label to a file in Word, Excel or PowerPoint, go via Start to ‘Sensitivity’ in the top ribbon. There, you can activate one of the four labels. In Outlook, you will find the ‘Sensitivity’ button on the right in the message window. 

When to apply a label?

Labels should be applied to documents  that contain data that fit the sensitivity types as described in the table. It concerns files that you save or share in OneDrive and Teams/SharePoint, and files that you create online and then save (online or locally). The label ‘confidential’ or 'secret' indicates that the document should be handled with care and, where necessary, the possibility to share or print it should be restricted. 

Questions?

If you have any questions, you can contact Functional Management Workspace via functioneelbeheer-werkplek@issc.leidenuniv.nl.