Over the past two decades, a leading business practice has been often-repeated rounds of downsizing and restructuring (also referred to as reorganization, re-engineering, and a host of other euphemistic terms) by large private and public sector employers. Frequently associated with other practices such as outsourcing, privatization, and the increased use of temporary workers, downsizing/restructuring has increased the level of job insecurity among workers as well as leading to changes in work processes (including work intensification and multi-tasking) and management behavior. How has downsizing/restructuring and increased job insecurity affected the occupational health, safety, and well-being of workers, and what measures have employers, unions, and governments taken to address any adverse effects? The authors reviewed international studies of the occupational health and safety (OHS) effects of downsizing/restructuring and increased job insecurity undertaken over the past 20 years. After imposing quality filters, they obtained 86 studies. Analysis revealed that 73 (85%) of the studies found poorer OHS outcomes (using a range of measures). Studies were examined to see whether they provided clues as to the reasons for negative outcomes.