Purchasing decisions in industrial goods markets are typically made not by individuals, but collectively by buying centers. Consequently, the analysis and forecasting of these decisions are quite complex. The focus is less on methodological aspects and more on generating the necessary data for analysis. Jörg Brinkmann examines, using decision-making processes in the construction industry as an example, to what extent the problem of data generation can be solved when the company's own sales representatives are surveyed instead of the customers. Building on the considerations of principal-agent theory, he demonstrates through a comparison of direct and indirect, conjoint analytical measurement methods which approaches are particularly suitable for sales surveys. Furthermore, he analyzes the extent to which personal characteristics of the sales representatives also have an impact.