Data loss prevention - where to start?

Does anyone have any recommendations for capturing requirements for different departments for DLP? Planning to implement using Microsoft DLP tools and working through a data register to capture what data types each department manages. The next step is to define and start testing some policies but wondering where to start. Ideally we are going to start simple based around sensitive data and gradually roll out from there - does anyone have any recommendations? What types of policies have you focused …

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