The use of policy instrument in combination. If a government has only one objective, it will often be possible to achieve it using only one policy instrument. If more than one policy instrument is available, and use of each involves adverse side-effects which increase more than proportionally as it is used more, it may pay to use a mix of policy instruments to reduce these side-effects. If the government has more than one objective, as it always has, at least n independent policy instruments are needed to allow n separate objectives to be obtained, other than by coincidence. This too dictates using a mix of policy instruments. If more than n instruments are available, the mix should again be chosen to reduce total adverse side-effects.

• purchasing power parity
• pure floating exchange rate
• put option
• pyramid scheme
• q, Tobin's
• quadrant
• quadratic
• qualification of accounts
• quality control
• quality ladder
• quality standards
• quango
• quantity and price adjustment
• quantity demanded
• quantity discount
• quantity equation
• quantity of money
• quantity supplied
• quantity theory of money
• quarterly data
• quartile
• quasi-autonomous non-government organization
• quasi-rent
• queue
• quits