Amazing Experience!
I had a great trip with Norbu and Adventures in Tibet. The people are great--very kind, professional, and fun travel partners for side trips and tours. Papers and clearances were all taken care of and no issues at all, which was comforting. There can also be a lot options and flexibility for itineraries if you want to make special requests. I had some very specific historical and religious sites/places that I was interested in that were a bit off the conventional tourist path, and Norbu helped me set up some visits that were very meaningful to me.