Due to the country's poor economy, Peruvians travel by more by bus than other form of transportation, and so do most of its tourists.  Bus travel across is inexpensive, but the quality of the busses varies, as do rates according to season.  The higher-priced lines, such as Cruz del Sur and Ormeño, offer cleaner, safer, and more comfortable seating, as well as faster service, but one should never be complacent regarding the potential of theft no matter what bus one is on in. Busses traveling between large cities routinely sell-out so it is recommended that you purchase you ticket at least a day in advance. The larger busses do have toilets, but they are often out-of-order and rarely cleaned, but if you talk to the driver, he will generally wait for you if you explain that you need to use a bathroom at a stop.  Many busses between major tourist destinations only leave at night, so bringing a blanket is advised both for sleeping and keeping warm. Below is a list of bus companies in Peru: 
1.       Oltursa--www.oltursa.com.pe

2.       Cruz del Sur--www.cruzdelsur.com.pe

3.       El Dorado--www.transporteseldoradopiura.com

4.       Línea--www.transporteslinea.com.pe

5.       Civa--www.civa.com.pe

6.       Ormeño--www.grupo-ormeno.com.pe

7.       Transportes Chiclayo--www.transporteschiclaypo.com

8.       Soyez--www.soyuz.com.pe

9.       Peru Bus--www.perubus.com.pe