Delete Dynamics 365 Data – Based on an import “Hack”!

I recently saw a "trick" with Dynamics 365 that I thought was quite cool. So, I decided to document it in a blog post. This must be a reasonably common scenario! Our sales team want to purge the system of some old contacts. They were given a spreadsheet listing all the existing data. And people marked the ones that needed to be deleted. Great! But how do I easily remove these contacts from our Dynamics 365 instance.