This book constitutes the refereed proceedings of the 9th International Workshop on Perinatal, Preterm and Paediatric Image Analysis, PIPPI 2024, held in conjunction with the 27th International Conference on Medical Imaging and Computer-Assisted Intervention, MICCAI 2024, in Marrakesh, Morocco, on October 6, 2024.

The 14 full papers presented in this book were carefully reviewed and selected from 17 submissions. The methods presented in these proceedings cover the full scope of medical image analysis including segmentation, registration, classification, reconstruction, population analysis and advanced structural, and functional and longitudinal modeling, all with an application to younger cohorts.