John Sader’s development of pioneering measurement techniques has revolutionised the characterisation of materials using the Atomic Force Microscope (AFM). His scientific contributions are widely used and have enabled breakthrough discoveries in materials science at the molecular and atomic scale. The Sader Method is an international standard for AFM force calibration as is the Sader-Jarvis Method for atomically resolved AFM force measurements. These methods appear in textbooks and are used in commercial instruments. He has also made important contributions across an array of fields, including nanomechanics, plasmonics, rarefied gas dynamics and fluid-structure interactions ranging from nano- to macro-scales.