The National Association of School Nurses' research priorities include the recommendation that data reliability, quality, and availability be addressed to advance research in child and school health. However, identifying a national school nursing data set has remained a challenge for school nurses, school nursing leaders, school nurse professional organizations, and state school nurse consultants. While there is much agreement that school nursing data (with associated data integrity) is an incredibly powerful tool for multiple uses, the content of a national data set must be developed. In 1993, recognizing the unique power of data, Massachusetts began addressing the need for consistent school nurse data collection. With more than 20 years' experience--and much experimentation, pilot testing, and system modification--Massachusetts is now ready to share its data collection system and certain key indicators with other states, thus offering a beginning foundation for a national school nursing data set.