How to combine/join two reports - Lead History and Lead Activity History?

Hi Ajay,

This isn't going to be possible the way you defined it

Lead History report primary object is Lead History
Lead Activity History report primary object is Task (Activity)
Hence, no common object to join

Because there is no common object, but a conceptual common Lead.Id, you might be better off writing a simple APEX VF controller and VF page to do the joins in memory into a single wrapper class. You'll need to think about what your layout is going to look like as for a given lead, there are n field histories and m activities

Thanks