Vulnerable or susceptible groups are mentioned in most reviews and documents regarding noise and health. But only a few studies address this issue in a concrete and focused way. Groups at risk most often mentioned in the literature are children, the elderly, the chronically ill and people with a hearing impairment. The other categories encountered are those of sensitive persons, shiftworkers, people with mental illness (e.g., schizophrenia or autism), people suffering from tinnitus, and fetuses and neonates. The mechanism for this vulnerability has not been clearly described and relevant research has seldom focused on the health effects of noise in these groups in an integrated manner. This paper summarizes the outcomes and major conclusions of a systematic, qualitative review of studies over the past 5 years. This review was prepared for the 10 th Conference on Noise as a Public Health Problem (ICBEN, 2011). Evidence is reviewed describing effects, groups assumed to be at risk, and mechanisms pertaining to noise sensitivity and learned helplessness.