Purpose: This thesis focuses on IMC research, a concept that has had a strong development in recent years, mainly from the emergence of new technologies and a change in the methods in which the companies communicate with the consumers. In the first part of this study, the different IMC contributions are reviewed. Next comes an analysis of both companies, our object of study, finishing with a rivalry analysis between Coca-Cola and Pepsi. This paper stands out for the its originality in studying the perception of consumers in the use of Integrated Marketing Communications in Coca-Cola and PepsiCo, two large multinational companies, and between the two countries of Spain and the U.S.A. Design / Methodology This research has been undertaken in the Spanish and U.S. markets. In the first place, the perception of the quality of communications of these companies by the industry professionals is analyzed. The consumer's perception was analyzed next, in order to compare same to that of the professional’s, and to demonstrate the validity of the model utilized. Two questionnaires were prepared: a simpler one for professionals that was collected on the streets of New York and Valencia, and another one for consumers that was realized in Spain and the U.S.A. through an online platform. Findings: It may be concluded that the selected group of items accurately determine whether or not a company manages its marketing communications as Integrated Marketing Communications 1 0 Integrated Marketing Communications. After validating the model used, based on the different previous studies published, the perception similarity between consumers and professionals has been demonstrated. Research limitations: The study has been developed for two countries, and for two specific brands, which might be a limitation. Thus, distinct questionnaires for professionals and consumers were used, despite the validation of the model used. Practical implications: The conclusions of this thesis could lead to future research that strengthens the understanding that the consumers have about integrated marketing communications made by companies, and how being a user versus a heavy user may influence said perception. The study of both markets allows us to compare the consumers’ image of the two brands, concluding that there are hardly any differences between the consumers of both countries. The differences depending on the brand consumed and in heavy users have also been analyzed, concluding that these factors hardly influence the consumer’s perception of the IMC of the brands studied. Originality / Value: This paper’s valuable contribution resides in the research uniqueness and originality, as it is conducted in two different markets, and compares industry professionals with consumers. Additionally, we undertake an analysis of the perception in function of someone being a consumer of a brand, or by being a heavy user.