Vladimir Fonov, Alan C. Evans, Kelly Botteron, C. Robert Almli, Robert C. McKinstry, D. Louis Collins, and the Brain Development Cooperative Group developed unbiased, age-appropriate MRI atlases for pediatric studies. These atlases, created from a large, representative sample of children aged 4.5–18.5 years, provide high-resolution anatomical details and are designed to reduce bias in pediatric brain imaging analysis. The study used a combination of nonlinear registration and iterative averaging to generate templates for T1-weighted, T2-weighted, and proton density-weighted MRI scans, along with average tissue maps for gray matter, white matter, and cerebrospinal fluid. The atlases were validated using deformation-based morphometry, demonstrating their effectiveness in reducing bias when analyzing pediatric data. The templates are publicly available and can be used for both clinical and research purposes, enabling standardized comparisons across studies. The study highlights the importance of age-specific templates in pediatric neuroimaging, as adult templates may introduce bias due to differences in brain development. The developed atlases represent a significant advancement in the field, providing a reliable reference for analyzing brain structure and function in children.Vladimir Fonov, Alan C. Evans, Kelly Botteron, C. Robert Almli, Robert C. McKinstry, D. Louis Collins, and the Brain Development Cooperative Group developed unbiased, age-appropriate MRI atlases for pediatric studies. These atlases, created from a large, representative sample of children aged 4.5–18.5 years, provide high-resolution anatomical details and are designed to reduce bias in pediatric brain imaging analysis. The study used a combination of nonlinear registration and iterative averaging to generate templates for T1-weighted, T2-weighted, and proton density-weighted MRI scans, along with average tissue maps for gray matter, white matter, and cerebrospinal fluid. The atlases were validated using deformation-based morphometry, demonstrating their effectiveness in reducing bias when analyzing pediatric data. The templates are publicly available and can be used for both clinical and research purposes, enabling standardized comparisons across studies. The study highlights the importance of age-specific templates in pediatric neuroimaging, as adult templates may introduce bias due to differences in brain development. The developed atlases represent a significant advancement in the field, providing a reliable reference for analyzing brain structure and function in children.