The purpose of this study was to examine the use and outcomes of quality improvement activities among early childhood education programs participating in the Iowa Quality Rating System (Iowa QRS). The study summarized survey responses from 388 program administrators, describing how staff of programs in Iowa QRS participate in quality improvement activities such as training, coaching, and continuing education. The study also used logistic regression analysis to examine the relationship between quality improvement activities and increases in Iowa QRS ratings, in a subset of 146 programs that received Iowa QRS ratings at two different points in time. Survey responses indicated that almost all programs had staff participate in trainings and a majority of programs offered coaching, but participation in continuing education was less common. The most common topic of professional development was health and safety practices, followed by child development and classroom practices. Analysis results found that Iowa QRS ratings tend to increase across time, and programs that provide key staff with 15 or more training hours per year are more likely to increase ratings over time than programs that do not. The results also suggest that topics covered in professional development are important, with both positive and negative relationships observed between different professional development topics and rating outcomes. The study findings can help Iowa QRS administrators plan and allocate resources to support programs’ quality improvement efforts. The findings also can help administrators in other states better understand the types of quality improvement activities to which programs are drawn naturally, as well as factors that may facilitate or impede programs’ pursuit of quality.