Practice-based research networks at the crossroads of research translation.

Practice-based research networks (PBRNs) are "experimental farms" for research that matters in clinical practice. One of the defining characteristics of PBRNs is their ability to operate across a wide range of the bidirectional "pipeline of research translation," from clinical trials to informing health care policy. Developing effective translational approaches requires significant experimentation with new or innovatively combined research methods and theoretical frameworks. While the first decades of PBRN research generated a substantial body of evidence for improving individual practices (horizontal movement), PBRNs now find themselves at the multidimensional crossroads of patient-centeredness and community/population health (vertical movement). This practice-based research theme issue of the Journal of the American Board of Family Medicine provides a rich, cross-sectional synopsis of PBRN activities encompassing T2 translation, core practice-based research, implementation and dissemination research, community practice, and contributions to health care policy.