Abstract: A method and system for collecting data on a user of communication device into a customer register. A product of a consumer carries out active marketing by transmitting a product code to its environment. The user of the communication device receives the product code when he retrieves the product data corresponding to the product code from a server or when he performs a purchase operation concerning the product to which said product code refers, data on the user of the communication device are stored in the customer register and a reward is formed to the consumer on the basis of the realized retrieval of said product data, or said purchase operation and the product code referring to the identity codes of the consumer.