Free-market economists adamantly disagree with the notion that mass unemployment is possible in a completely free labor market. Ludwig von Mises went as far as to claim that in a free market such thing as involuntary unemployment is impossible, since if one offers his labor for low enough a price he will always find a buyer.[17] Of course, knowing that the market is in constant disequilibrium, one recognizes that involuntary unemployment is not necessarily impossible but simply rare and based only on imperfect information.[18] In short, outside of the existence of imperfect information, in a free-market the only limitation to employment is an individual's reservation wage.
Generally speaking, involuntary unemployment must be a product of government interventionism.[19] At its basis, involuntary unemployment is a product of disequilibrium between demand for labor and supply of labor, where the aggregate price of labor is too high relative to the aggregate demand for labor.[20] It stands to reason that such disequilibrium is likely to happen in the event of a cyclic fluctuation and from there we can logically deduct that the most efficient remedy to high unemployment is a fall in wages.
As mentioned above, the Keynesian framework tends to regard long-term structural unemployment as involuntary. The reason why an individual, who has been unemployed for what we assume to be a very long time, cannot find a job is because his skills are no longer applicable to the trade he is looking in. Such unemployment is actually voluntary in nature, because while the individual may not be able to find a job with similar pay to his last, there are nevertheless employers looking for labor in industries that require less skill, even if these employers therefore offer a lesser wage. Or an employer may offer the individual a lesser wage, but in exchange offer him the relevant training necessary to acquire the demanded skills. The individual rejects this offer because it is under his reservation wage. As such, this type of unemployment is firmly voluntary.