Ilona Johnson, PE, is the Director of Design and Engineering at Harris Design Studio in Arlington, VA, where she brings 18 years of experience spanning energy consulting, commissioning, and HVAC design. In her role at Harris, she leads the design of mechanical and plumbing design/build projects across diverse sectors, including mission-critical environments such as data centers. She also collaborates with multidisciplinary teams on design-assist projects to help optimize project delivery. She focuses on creating high-efficiency building systems and leveraging offsite manufacturing and prefabrication strategies to improve performance, speed, and cost-effectiveness. As part of Harris—a leading national mechanical contractor with a strong culture of collaboration and technical excellence—she contributes to the delivery of integrated, forward-thinking design solutions that align with client goals and project demands. Ilona holds a bachelor’s of science degree from Smith College and a master’s in mechanical engineering degree from University of Maryland.