This is a summary of a dissertation which focuses on the relationships between the Marketing and Sales departments, exploring specific organizational and functional factors as sources of Marketing-Sales conflict, as well as the consequences of this conflict on company performance. Based on the data collected from both Marketing and Sales managers of 132 consumer goods’ companies, the dissertation identifies as sources of Marketing-Sales conflict (a) the low degree of market orientation, (b) inconsistencies in the perceptions of Marketing and Sales managers regarding their respective companies strategy, (c) the unequal level of power between the Marketing and Sales departments, (d) differences in the perceptions of Marketing and Sales managers regarding the importance of basic marketing activities, and (e) the low quality of cooperation between M&S departments for the execution of these activities, and as a consequence of this conflict the reduced company performance. The implications of the dissertation are discussed.