Growth factors (GFs) are a class of proteins that bind to specific cell surface receptors (GF-Rs), inducing a variety of responses including mitosis, in susceptible target cells. Abnormal production, expression, and/or function of GFs or GF-Rs can result in unregulated growth, the hallmark of malignant transformation. This chapter reviews those GFs/GF-Rs that have been linked to human bladder cancer. It focuses particularly on one [epidermal growth factor (EGF), which is excreted in urine in high concentrations] and its possible role in the development and growth of urothelial malignancy. Potential clinical applications in diagnosis, staging, prevention, and treatment are discussed.