Abstract: The claimed invention relates to a system and computer implemented method for quantitatively measuring effectiveness of a marketing campaign or marketing strategy execution. The client device accesses the server over a communications network to define targeted customer segments based on the marketing campaign or a specific set of marketing objectives and to define a quantifiable outcome or payoff for each targeted customer segment of the client, thereby linking the performance of client's marketing campaign or objectives to the quantifiable outcome for each targeted customer segment. The server generates behavior paths for each targeted customer segment on a client website for effective measurement of adherence of a website visitor/customer to the behavior paths leading to the quantifiable outcome. The rules engine calculates a path score to determine whether the customer adheres to or diverges from a preferred behavior path established for the customer's targeted customer segment.