I welcome Dr Charles' comments because they highlight a major point made in the paper, namely that occupational disease and injury are underestimated. Dr Charles points out that there is a limitation in using only the published literature, which is peer-reviewed, as was done in this paper. However, most journals only consider papers that use the published literature. Indeed, a much fuller picture might be developed if gray literature and internal reports of insurance companies and corporations were available for review. The question is one of what journals will accept and also of what is available to researchers. The gray literature is often not peer-reviewed or easily accessible. It may not be appropriate to characterize the sources of burden information as inconsistent; they are just different. Different tools are used to measure morbidity and mortality on the population-level as opposed to the company level. Ideally, it would be helpful if every employer used the same methods to track (in census terms) their working populations, and monitor and characterize their health, illness, injury, and disability status. However, from the perspective of public health surveillance, a central database and standardized methods of data collection, analysis, and reporting may be difficult to achieve. Among the additional steps that Dr Charles suggests for improving estimation of the burden is the statement to engage workers in accurate reporting and for them to be willing to assume personal responsibility for their safety. Such a recommendation, in the absence of any discussion of employers' responsibilities regarding workplace safety and health, is incomplete.