Entrepreneurial Orientation (EO) and Market Orientation (MO) are considered key factors in ensuring firm longevity in the new competitive landscape. Despite extensive research during the past decade, most of the studies use samples that exclude small and medium enterprises (SMEs), which represent the majority of economic activity worldwide. Some studies do investigate this relationship in small companies but place little importance on the subtle differences between SMEs and large companies when measuring MO. This study empirically investigates the relationship between MO and EO on a sample of 2500 Swedish SMEs. A new measure of MO that takes into consideration SMEs specific conditions has been developed and used. Findings suggest that MO is the main determinant of EO in SMEs.