Before analyzing Wal-Mart's corporate strategy, it is important to decide what business it is in. For example, if Wal-Mart is in the business of selling consumer goods such as TV's, sheets, clothes, etc then it is pursuing a concentric strategy by entering the food business. However, this changes depending on how you analyze what business Wal-Mart is in. Wal-Mart is in the business of selling everything customers need in their everyday lives. This includes the consumer goods listed above as well as food-service items. Even still, Wal-Mart pursues multiple strategies. Concerning concentration, Wal-Mart continually finds more consumer goods to sell at its stores which can take money from competitors. Additionally, when Wal-Mart entered into the food market, it quickly consolidated and held to good, saleable products. Wal-Mart never forays too far into a market and only sells what will make it a profit.
Lastly, an argument can be made that Wal-Mart is also pursuing a vertical integration strategy. Wal-Mart has developed its own name brand to sell products called Sam's Choice. This puts Wal-Mart into the business of making things like soda, cereal, and dog food. While they still don't grow their own crops or raise their own livestock, it is still a form of vertical integration. Also, Wal-Mart works heavily with its suppliers. This symbiotic relationship can be see as vertical integration due to the level at which Wal-Mart analyzes its suppliers and improves their manufacturing processes, etc.
Wal-Mart definitely has the business strategy of Low Cost Leadership ...