Resources which are available for use on a continuing basis, for example tidal power. These are contrasted with depletable resources, which are used up when used at all, and must eventually run out. Unfortunately we do not always know whether resources are renewable, which may depend on the intensity of use. Underground water resources, for example, are renewable if pumping is restricted to what is replaced by rainfall, but can be destroyed by over-extraction, leading to drying up or replacement of fresh water by sea-water. Some resources which are in principle depletable, in fact exist in such large quantities that any possible exhaustion date seems very remote. It is almost certain, for example, that civilization as we know it will come to a bad end for some other reason before it runs out of deposits of iron ore.

• 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