The tendency for any contract offered to all comers to be most attractive to those most likely to benefit from it. For example, if an insurer offers health insurance without any medical examination, the expectation is that people with poor health prospects are likely to accept it, while people with better health prospects, who can get better terms from a more selective insurer, will reject the unconditional contract. In trying to be non-selective, adverse selection causes the worst risks to select themselves.

• social benefit
• Social Chapter
• social charges
• social cost
• socialism
• social opportunity cost
• social overhead capital
• social safety net
• social security benefits
• social security contributions
• social services
• social welfare function
• society, co-operative
• soft budget constraint
• soft currency
• soft landing
• soft loan
• soil erosion
• sole proprietor
• sole trader
• Solow growth model
• Solow residual
• solution
• solvency
• sound money