A national sample of 2,048 workers was asked to rate the impact of their job on their physical and mental health. Ordered logistic regression analyses based on social ecology theory showed that the workers' responses were significantly correlated with objective and subjective features of their jobs, in addition to personality characteristics. Workers who had higher levels of perceived constraints and neuroticism, worked nights or overtime, or reported serious ongoing stress at work or higher job pressure reported more negative effects. Respondents who had a higher level of extraversion, were self-employed, or worked part time or reported greater decision latitude or use of skills on the job reported more positive effects. These findings suggest that malleable features of the work environment are associated with perceived effects of work on health, even after controlling for personality traits and other sources of reporting bias. Work and health are intimately connected, yet the complex association between multiple features of employment arrangements and workers' health is not well understood. Given the dramatic labor supply and demand changes in the past decade, better identifica- tion of the employment characteristics that underlie the health of workers is of profound practical impor- tance. As outlined by the National Occupational Re- search Agenda (National Institute of Occupational Safety and Health (NIOSH), 1996), the changing nature of jobs (e.g., shift from manufacturing to ser- vices) as well as the aging and growing diversity of the workforce suggests that the threats to worker