There has been a shift in emphasis in public health from the provision of personal health services for individuals to efforts targeted at improving the health of the whole community. Many in public health nursing (PHN) have welcomed this shift, recognizing the important role PHN can play in promoting health and preventing disease for all. There continues to be a need to redefine PHN roles and practice so that public health nurses can participate more effectively. Los Angeles County Department of Health Services Public Health Nursing (LAC PHN) has developed a practice model grounded in nationally recognized components: the public health team, PHN standards of practice, the 10 Essential Public Health Services, Healthy People 2010's 10 Leading Health Indicators and additional local indicators, and the Minnesota Public Health Nursing Interventions Model. The LAC PHN Practice Model provides a conceptual framework that assists in clarifying the role of the public health nurse and presents a guide for public health practice applicable to all public health disciplines.