Foreign and Taiwanese travelers need to first apply for special permissions to make a Tibet tour. At present, they are not allowed to make such trips individually. But those who only want to visit Lhasa in Tibet are now allowed to travel on their own.
Foreign diplomats and journalists cannot apply for tourist permission to visit Tibet -they should apply through formal diplomatic channels instead.
Approval of Tibet travel applications usually takes a week. Tourists should report their entire tour itinerary to the authorities.
The Tibet Tourism Bureau Shanghai office is responsible for granting travel permission to foreign and Taiwanese tourists in Shanghai and neighboring provinces.
 Walking tours or off-road tours are not yet permitted for foreigners in Tibet.
What documents should I hold for traveling in Tibet?
There are two documents required for foreign tourists who want to travel in Tibet: a Chinese Visa and a Foreigner's Travel Permit issued by the Tibet Tourism Bureau.

How do I get the permit? 
Your Chinese tour agent can be your representative to apply for the permit. But do contact them in advance and give them enough time for the paperwork. The Tibet permit can be issued two weeks prior to your entry into Tibet.

Is independent travel allowed in Tibet?
Not yet. You must be part of an organized tour group. In short, you must have a tour under the supervision of a tour agency in China.
The tour agency is responsible for your Tibetan trip, even if you only need a hotel reservation or a private car renting.

Can I fly direct to Lhasa without the permit?
No, the Tibet permit must be obtained beforehand through Chinese tour agencies in China or Chinese counsel in your native country