This chapter discusses the design and operation of pilot plants. It starts with an overview of operational concepts and processing requirements. It then summarized key concepts associated with the design of process equipment, product and non‐product contact utilities (including HVAC), containment, instrumentation, automation and control, data acquisition and archiving, warehousing, backup systems/redundancy, and future expansion/modification. This leads into a discussion of operating practices associated with maintenance, staffing, laboratory support, standard operating procedures (SOPs), safety, training, validation, and facility records including manufacturing execution systems (MES). Current best practices are presented for each topic, evolving from experiences from an industrial pilot plant. References associated with each topic area offer interested readers the opportunity to obtain additional information if desired.