Peru: Transportation

Public transportation is very easy in Peru; many taxis, mototaxis, buses....

Inside cities:
numerous and very cheap (often 3 to 5 soles, less than a metro ticket in Paris); more expensive in Lima (10 soles typically)
very cheap also
 Moto taxis in Casma
-bus inside Lima:
around 1 sol; there is a huge number of buses; they stop at every intersection and a guy is shouting the destinations. We regularly took buses without seing anything such as pickpockets, contrarily to what is being explained in the touristic guides.

Between cities:
-many bus companies,
from luxury "bus cama" to the basic ones. In some cities (Lima, Trujillo), each company has its own terminal.  In others,  a convenient global bus terminal (Arequipa, Puno, Cuzco) allows to compare the schedules; at the counters the employees are shouting loud the destinations of the next departures in order to try to fill the bus.
We had only one small problem with the most expensive one: a tire exploded, which led to a one-hour delay. With the most basic companies (we were often the only 2 tourists in the bus), we never had any trouble. Schedules are more or less reliable: on a 6 to 10 hours trip, a 30mn delay is often unavoidable. During the travel, a DVD is often playing, which allows to sample the worst films ever... or sometimes the worst peruvian pop-singers... We also had twice a guy doing advertisement for some products he would then sell on the bus (like ginseng, which according to this guy could cure more or less every possible disease, or cheap necklaces).
-air travel:
more expensive. Inside Peru we traveled once with LAN Peru and once with Aerocondor; in both cases the planes were on-time, with absolutely no problem.