Protecting millions of workers from occupational hazards frequently involves the use of respirators, protective clothing, gloves, or other personal protective technologies. The Personal Protective Technology Program at NIOSH is the fifth report in the series Reviews of Research Programs of the National Institute for Occupational Safety and Health. Taking into account several important factors beyond the program’s control, the committee found that since 2001 (the period covered by this review), the Personal Protective Technology Program has made meaningful contributions to improving worker health and safety through its work in priority areas that are highly relevant to improvements in workplace protection. To enhance the relevance and impact of the program’s work, the committee recommended that the NIOSH Personal Protective Technology Program take a comprehensive approach to the research, standards development, and certification across all types of occupational personal protective technologies; establish research centers of excellence; expedite the revision of respirator certification regulations and other enhancements to respirator certification; increase research on human factors issues; and emphasize pre- and post-market testing of protective products.