Since the 1960s the performance of research, especially in universities, has relied more and more on a growing population of postdoctoral scholars.
The size of the postdoctoral population has increased without a parallel increase in the number of academic faculty positions.
Postdoctoral experience is now seen as a virtual prerequisite for academic careers and many other research positions in the life sciences, physics, chemistry, and some other fields.
The postdocs themselves do not always achieve recognition, status, or compensation commensurate with their experience and skill.
Many postdocs remain in their positions for an indefinite number of years, beyond the five years or so during which they are reasonably considered trainees.
Many postdocs report frustration at not finding the employment positions they anticipated in return for their years of intensive effort.
The demographic characteristics of postdocs are changing. Many postdocs are in their middle to late 30s, with families that include children, and their medical and family support needs have increased.