Permanent employment, typical of industrial societies and bolstered by numerous social guaranties, has been declining in the past 2 decades. There has been a steady expansion of various forms of contingent work. The decomposition of traditional work is a logical consequence of the characteristic patterns of the knowledge-based economy. According to the logic of information technology, changeable modules are key characteristics of production processes and economic organizations. Each module leads a life of its own, with infinite combinatory possibilities. As a consequence, static and "safe" economic arrangements are replaced by dynamic and uncertain institutions. Employees (except for key personnel) become interchangeable, disposable, recallable, and transferable. Consequently, the portfolio of workers' capabilities and knowledge should be adjusted to the requirements of changing workplaces. For companies, the return on investments in employees' knowledge is uncertain; thus, contingent workers have to undertake, at least partly, the responsibility and costs of their own training. (Contains 4 figures and 13 notes.)