The private demand for a hypothetical vaccine that would provide lifetime protection against HIV/AIDS to an uninfected adult was measured in Guadalajara, Mexico, using the concept of willingness to pay (WTP). A 91-question survey instrument was administered by trained enumerators employing contingent valuation techniques to 234 adults, aged 18-60.

A contingent valuation survey was conducted in Kumasi, Ghana, to estimate households' willingness to pay for two types of improved sanitation services: improved ventilated pit latrines and water closets connected to a sewer system. Over 1200 randomly selected households throughout the city were interviewed.