Relatively recently, internal communication received little attention from theorists, since they focused on external communication. The importance of internal communication is seen as the taker of responsibility for all internal exchanges of information between internal stakeholders at all levels. However, interdisciplinary cooperation in terms of internal communication is a significant issue for any organization running the R&D process. Different studies have already revealed strong links between communication and R&D success, but a lack of research continuity is visible, especially one relevant in practice. This article examines communication in the R&D process through the prism of decision making. It aims to take experience from R&D experts to supplement a list of decision-making methods used in the R&D process, which is compiled based on literature analysis. In the next stage of the investigation, the list of decision-making methods is used to determine the weights of the methods, which reflect the suitability of the decision-making methods in the R&D process. In the final stage of the investigation, differences in the evaluations of the US and German experts are presented, reflecting different experiences and differences in the conditions of the business environment.