Peggy McCardle is a linguist and a certified speech-language pathologist. She is currently the Acting Chief of the Child Development and Behavior Branch at the National Institutes of Health. McCardle is interested in ways to incorporate literacy practices supported by proven research into classroom instruction.

She has held university faculty and hospital-based clinical positions, and has published articles addressing various aspects of developmental psycholinguistics and public health issues.

At NIH, she has served as a scientific review administrator and a senior advisor to the Deputy Director for Extramural Research in the Office of the NIH Director.

Early in her career, McCardle was an elementary classroom teacher.