Appointment slots?

[cgk]

Is it possible to create appointment slots in Outlook/Office365/any other paid service that MS provides that allows the user to provide calender slots in the same way that google calender does?

Let me be clear about this - I'm not asking how another member of my organisation makes an appointment request with me - I'm talking about the ability to make 30 minute slots (or whatever time I like) that people can see on a publicly available calender and book out.