Objectives. To evaluate the Public Health Emergency Preparedness (PHEP) program’s progress toward meeting public health preparedness capability standards in state, local, and territorial health departments. Methods. All 62 PHEP awardees completed the Centers for Disease Control and Prevention’s self-administered PHEP Impact Assessment as part of program review measuring public health preparedness capability before September 11, 2001 (9/11), and in 2014. We collected additional self-reported capability self-assessments from 2016. We analyzed trends in congressional funding for public health preparedness from 2001 to 2016. Results. Before 9/11, most PHEP awardees reported limited preparedness capabilities, but considerable progress was reported by 2016. The number of jurisdictions reporting established capability functions within the countermeasures and mitigation domain had the largest increase, almost 200%, by 2014. However, more than 20% of jurisdictions still reported underdeveloped coordination between the health system and public health agencies in 2016. Challenges and barriers to building PHEP capabilities included lack of trained personnel, plans, and sustained resources. Conclusions. Considerable progress in public health preparedness capability was observed from before 9/11 to 2016. Support, sustainment, and advancement of public health preparedness capability is critical to ensure a strong public health infrastructure.