This article discusses the use and the ways of assessment of the internet as a source of information due to the agility that this way has been providing to the Marketing Information System, which also shows to be fragile in terms of reliability of the available information The study consists of an exploratory research, which includes literature review and multiple case studies, and presents as its objective the understanding of how the internet is used in the processes of data source definition and evaluation in a company, from the user's point of view. The results indicate that the internet is an important source of information, but there is little systematization in the information collection and the sources evaluation is based only on the users' individual and practical knowledge.
Marketing Information Systems; Data Sources; Information; Internet; Reliability