Sky burial was once a common practice in Tibet, until it was outlawed in the 1960s by the Communist government. Today it is legal again, but is a very uncommon method of burial, except for in smaller mountain towns.
Monks would chant mantra around a deceased person's body and burn juniper incense the day before the rogyapas, or body-breakers, would come in. The rogyapas' job was to disassemble the body. They are unusually calm, even happy and light-hearted as they carried out their task. Supposedly this makes the soul of the deceased pass on to the afterlife more smoothly.
After preparation, the body would be put on a stake in the mountains for the vultures to eat, sometimes while the deceased's family watched. After the flesh was picked off of the bones, a rogyapa would crush the skeleton of the deceased and grind the bones with tsampa, leaving it for crows and hawks to eat.
Why do they do this? Buddhism teaches generosity and compassion, and therefore, after death, it is only fair that your body, which you no longer possess, should be given to someone who needs it more - in this case, the vultures. Some eyewitnesses have claimed it is to bring the deceased's body closer to their soul in the afterlife.
It may seem bizarre, even grotesque, to us in the Western world, but perhaps the Tibetan Buddhists are aware of something we are not. Perhaps it would be best to learn from them.