This open access book details tools and procedures for data collections of hard-to-reach, hard-to-survey populations. Inside, readers will discover first-hand insights from experts who share their successes as well as their failures in their attempts to identify and measure human vulnerabilities across the life course. Coverage first provides an introduction on studying vulnerabilities based on the Total Error Survey framework. Next, the authors present concrete examples on how to survey such populations as the elderly, migrants, widows and widowers, couples facing breast cancer, employees...