To use aggregated data from health informatics systems to identify needs of maternal and child health (MCH) clients served by county public health agencies and to demonstrate outcomes of services provided. Participating agencies developed and implemented a formal standardized classification data comparison process using structured Omaha System data. An exploratory descriptive analysis of the data was performed. Summary reports of aggregated and analyzed data from records of clients served and discharged in 2005 were compared. Client problems and outcomes were found to be similar across agencies, with behavioral, psychosocial, environmental and physiological problems identified and addressed. Differential improvement was noted by problem, outcome measure, and agency; and areas for enhancing intervention strategies were prioritized. Problems with greatest improvement across agencies were Antepartum/postpartum and Family planning, and least improvement across agencies were Neglect and Substance use. Findings demonstrated that public health nurses address many serious health-related problems with low-income high-risk MCH clients. MCH client needs were found to be similar across agencies. Public health nurse home visiting services addressed important health issues with MCH clients, and statistically significant improvement in client health problems occurred consistently across agencies. The data comparison processes developed in this project were useful for MCH programs, and may be applicable to other program areas using structured client data for evaluation purposes. Using informatics tools and data facilitated needs assessment, program evaluation, and outcomes management processes for the agencies, and will continue to play an integral role in directing practice and improving client outcomes.