Reilly’s model and law refers to a theory developed by American geographer William J. Reilly in the early 20th century. This model and law states that the location of a retail store is determined by the balance between the cost of land and the potential sales that can be generated from that location. In other words, the closer a store is to its target market, the higher the cost of land will be. This concept is often used in urban planning and retail site selection to determine the most profitable and efficient locations for businesses. Reilly’s model and law has been influential in shaping the development of cities and the retail industry, and continues to be a relevant and valuable tool in modern business strategies.