Aliens' Travel Permits are issued by the PSB and give you permission to visit specified places within specified time limits. They cost ¥10 (sometimes plus ¥1 for the form). At the time of writing the only parts of Tibet where you did not need an Aliens' Travel Permit were Lhasa, Shigatse, Zhangmu and Tsetang. For all other areas you need to apply to the PSB in the district capital for a permit. There are some areas where a permit will not be given under any circumstances, such as the highly militarized Chumbi Valley. However, the status of other areas seems to change from one day to the next. Being caught somewhere without a permit can be fairly heavy: travellers have faced big fines, confiscation of passports, been harangued at length and forced to write "confessions". In practice, there are some areas without checkposts on the way and no PSB officers at your destination, for example Namtso Lake, and there's little point in alerting the PSB to the fact you're going.

The public transport system in Tibet, such as it is, consists of large public buses and the smaller, nippier minibuses . For Tibetans these are largely interchangeable, but for foreigners the difference is highly significant. There are, as yet, no problems with foreigners travelling on the public buses, but minibuses come under the label of "private vehicles" and foreigners are banned from travelling on these (although the minibuses that operate within Lhasa itself seem exempt from this ban). This is regardless of the fact that minibuses are often the best, and sometimes the only, public transport between two points. This ban also means foreigners cannot travel in trucks and private cars which effectively rules out hitch-hiking. The zeal with which the PSB enforces this regulation, and hence the willingness of the drivers to take a chance and carry you, changes from month to month. The drivers face huge fines and big trouble if they are caught. The situation with regard to pilgrim buses seems even more confused. These are large buses, operating daily to Ganden and Tsurphu monasteries, and while most travellers report few problems, at times of particular tension or zeal by the authorities, drivers may be hesitant about taking you.

Most travellers end up renting a jeep , driver and/or guide (this last may be obligatory) for specific trips through one of the many private tour companies in Lhasa. All the hotels have agencies and they adorn Beijing Dong Lu and Mentsikhang Lu. You'll need to decide your exact itinerary, get together five people to fill up the jeep, write a contract detailing timings and costs and pay the deposit (usually half the agreed fee) before you go. The tour company should arrange permits and you should check the quote includes the cost of these plus fees, lodging and food for the driver and guide and the cost of fuel, in fact everything except your own food and lodging and the cost of your admission to monasteries. It pays to be precise in your itinerary (so, for example, don't say Rongbuk Monastery if you mean Everest Base Camp), as well as to work out what the extra cost should be if one of your party falls ill and you are delayed (about ¥200 a day is reasonable). The most popular option, a five-day tour to the Nepalese border taking in Gyantse, Shigatse and Everest Base Camp, should cost around ¥4000.

Hopefully you'll have no problems , but there have been sufficient misunderstandings between tourists and tour companies that the Tibet Tourism Bureau at 208 Yuan Lin Lu, Lhasa, has a Tour Service Inspection Office which handles complaints about tour companies (tel 0891/6333476 or 6334193).

Of the maps available, recommended is the Mapping Bureau of the TAR's English-language China Tibet Tour Map and Lhasa Tour Map. Both are available at the Xinhua Bookstore, where they cost ¥7, and at most hotels, where they are a little pricier. The Yak Hotel has a dated but detailed handrawn city map (¥3). See "Basics".