This thesis studies the impact of market orientation on the business performance of the Sri Lankan apparel manufacturing organizations in the post MFA environment. An attempt is made to enhance the existing market orientation theory by addressing a research gap and highlighting the importance of the relationship perspective in business to business marketing. A four dimensional market orientation construct is developed to overcome the limitations identified in the extant market orientation theories. The study also identifies resource availability as an antecedent of market orientation along with six other antecedents which are commonly discussed in literature. It further investigates whether the market orientation-business performance relationship is moderated by the prevailing business environment. The proposed modifications to the theory are empirically tested within the context of the apparel industry.