Techniques for improving and optimizing or attempting to optimize performance of messaging campaigns, particularly to marketing campaigns in which advertisements or other messages are distributed over an interactive measurable medium. When message is an advertisement, campaign involves a list of ad alternatives and a target customer population. Goal of message manager or marketing manager is to allocate ad alternatives to customer population to optimize business objectives such as maximizing the number of positive responses received. This is achieved by segmenting customer population into segments and then finding best allocation of ad alternatives for each segment. The number of segments and grouping of a customer population changes at different stages of the campaign. When the message is other than an advertisement, goal is to allocate messages to optimize analogous business or campaign objectives, typically measured by the number of successes or successful responses.