Health Economics traditionally involves two distinct strands. One focuses on the application of core neoclassical economic theories of the firm, the consumer and the market to health-seeking behaviour and other health issues. It suggests a role for government intervention only in the case of specific market failures (for example externalities, asymmetric information, moral hazard, and public goods) that distort market outcomes. The second strand is evaluation techniques, used to assess the cost effectiveness of competing health interventions.