The problem faced by parties to an exchange in which the terms offered by one party will cause some exchange partners to drop out. An example is the problem of asymmetric information in insurance: if the price is sufficiently high, the only people who will seek to purchase medical insurance are people who know they are ill (but the insurer does not). This will lead to further price increases to cover costs. Also referred to as the ‘hidden attributes’ problem (the state of already being ill is the hidden attribute), to distinguish it from the ‘hidden actions’ problem of moral hazard. See also: incomplete contract, moral hazard, asymmetric information.