Consumer behavior involves the psychological processes that consumers go through in recognizing needs, finding ways to solve these needs, making purchase decisions (e.g., whether or not to purchase a product and, if so, which brand and where), interpret information, make plans, and implement these plans. Consumers often buy products not because of their attributes per se but rather because of the ultimate benefits that these attributes provide, in turn leading to the satisfaction of ultimate values. The important thing in a means-end chain is to start with an attribute, a concrete characteristic of the product, and then logically progress to a series of consequences (which tend to become progressively more abstract) that end with a value being satisfied. Thus, each chain must start with an attribute and end with a value. An important implication of means-end chains is that it is usually most effective in advertising to focus on higher level items. A market comes into existence because it fulfills the needs of the consumer. Consumer behavior is a complex, dynamic, multidimensional process, and all marketing decisions are based on assumptions about consumer behavior. Models of consumer behavior play a key role in modern empirical Industrial Organization.