A central challenge in information systems development (ISD) is the question how meaningful and coherent requirements can be developed as a consensual result of the interaction between analysts and clients. As language-based communication is the main venue for the system‟s conceptualization, we assume that the understanding of how requirements emerge on the micro level of interaction is of critical importance. We claim that the quality of the communication between the different stakeholders depends on the ability to manage the question of how people deal with language in practice and reach consensus in the concrete ISD process. Therefore, in this paper we adapt the concept of quality to the question of how a common language is built in the ISD process. After defining a set of reasonable language quality dimensions, we apply our results to concrete observation cases from an ISD project and obtain insight beneficial to researchers and practitioners alike.