Requirements engineering for commercial off-the-shelf software packages entails special challenges. This paper presents preliminary results from an empirical study investigating these challenges through a qualitative approach using semi-structured interviews. The survey is exploratory with the objective of eliciting relevant topics for further research. Seven employees at five software companies with a market-driven development focus were interviewed. The areas of interest include process-related issues on release planning, requirements quality and decision support, as well as artefact-related issues regarding requirements as discrete entities and their representation. The paper also contains a characterization of each company, regarding aspects such as products, processes and customers. A number of challenging issues were elicited, including communication gaps between marketing and development, the problem of balancing the influence between marketing and development on requirements decisions, as well as the limited value of monolithic requirements specifications and the problem of requirements overloading.