1. Global Public Goods and Health: concepts and issues
David Woodward, Richard D Smith
What is a Public Good?
Public goods are goods which the "free market" will not provide because they are:
Most goods are private in nature: their consumption can be withheld until a payment is made in exchange, and once consumed they cannot be consumed again. For example, the consumption of a cake can be withheld from the consumer until the consumer pays the baker a price, and once the consumer has eaten that cake it cannot be eaten again. A private good is therefore considered excludable and rival in consumption. If purely private goods are seen as lying at one end of the spectrum of goods, at the other lie pure public goods, which are defined as having the opposite characteristics. That is, the benefits, once the good is provided, cannot be restricted and are therefore available to all (i.e. non-excludable), and consumption by one individual does not limit consumption of that same good by others (i.e. non-rival in consumption).