The challenge of viral marketing goes beyond determining the clients to read the message and consists of making them pass it on. This article presents the results of a research on consumer behaviour towards the “pass along” messages specific for viral marketing. The number of received/sent messages, the type of recipients, the conditions that a message has to fulfill so it can be read/passed along, the reasons for which messages aren’t passed along, all of these are variables analised in this study. The process of analising takes place on two different categories of consumers: The active consumers and the passive ones.