Bolivia is one of the safer countries in South America with regard to crime. Most of the cities are reasonably small and though people are poor, that’s considered normal and there are no rich people to rob. Consumerism hasn’t caught on in Bolivia like in other countries and Bolivian criminal types seem to lack the ambition to rob or kill for a new watch. Most people live simply and are content with there lives as such.
That doesn’t mean that Bolivia can’t be dangerous. The roads are awful and notoriously deadly from the mountains to the jungle. It’s very possible that the bus won’t have good breaks, or the driver might just be working all day and night and be taking coke to stay awake. Every year tourists die in the Salar de Uyuni when their van wrecks.
Bolivia also has about every disease imaginable, from dysentery, typhoid and cholera to the ubiquitous malaria of the jungle. You can even get lucky and catch an interesting disease like polio or plague in the remoter areas. Parts of Bolivia are still in the middle ages when it comes to sanitation…
Be careful with the food, which is rarely well prepared. Freshness is not highly valued by Bolivian cooks, so avoid street food, except in the morning, where good food like mazamorra de chicha morada and warm donuts can be had for a few cents each.
Women should also be on guard, as sexual assault does happen in Bolivia. Female travellers should dress conservatively and avoid going to bars alone at night. Really, common sense is the order of the day.
Cultural sensitivity is a necessity for travellers in Bolivia. Avoid taking photos of the local population without permission and in some cases you shouldn’t enter isolated communities without a local. Foreigners have been lynched. Overall, however, Bolivians are pretty relaxed and like respectful foreigners.