Hailing from Denver, CO, United States, John Kallemeyn is a data scientist for Marriott International. He received his degree in chemical engineering from the University of Colorado Boulder. John specialized in energy engineering and spent time in Germany researching cultural aspects of sustainability practices.

John began his career in upstream petroleum as a reservoir engineer, but had a change of heart after seeing the impacts oil & gas production had on the planet. Today, instead of oil pipelines, John builds data pipelines to measure carbon emissions (with an emphasis on supply chain emissions) and leverages data-driven strategy toward a sustainable future in the hospitality industry.