In December of 1939 McAn merged with J. F. McElwain Company because Ward Melville wanted to consolidate the entire production and marketing operation under one corporate head. In 1940 Melville posted sales topping $40 million for the first time. The growth continued unceasing until 1952, when total sales actually fell for the first time since the Depression. The decline from $92 million to $90 million signified the first inkling of a weakness in Melville's strategy. In an expanding and competitive economy, diversity and specialization became increasingly necessary. Accordingly Melville began to add more women's and children's shoes in an effort to diversify.
By 1967 sales topped $260 million. At the end of the 1960s, Melville was the nation's largest shoe retailer, operating 1,400 stores. In 1968 Melville made its most important move of the decade, opening the first of its Chess King stores, a clothing chain. The following year brought even more expansion. Melville bought three companies: the Consumer Value Stores (CVS) chain of drug retail outlets; Mark Steven, Inc., a firm that distributed products to CVS; and Retail Store Management, Inc.
In 1970 Melville, the fifth-largest and most profitable U.S. shoemaker, operated 1,644 total retail outlets. In 1972 Melville was ranked as the 43rd-largest retailing company in the United States, with sales of $512 million, and more than 15,000 employees.