An interview with Ana Henriques Correia, Tile Calorimeter System Project Leader, ATLAS Experiment at CERN by ATLAS colleague Steven Goldfarb (U of Michigan, U.S.A.). The ATLAS detector is built of many different components, each designed to measure properties of specific types of particles. Physicists need to know the type of particle, its direction and energy within the detector. This interview explains the Tile Calorimeter's role in measuring particles energies. Subjects include an introduction to the Calorimeter, what it is and its basic purpose, size, why it needs to be so heavy, how it measures hadrons, the construction of the tile calorimeter on a global scale both abroad and onsite by institutions and industry. Produced by: ATLAS OUTREACH Director: Yves-Rene Kayonga Director: Claudia Marcelloni 4:00 min