This study aims to reflect on the linguistic interaction in Spanish between doctors and patients. Specifically, we will analyze the discursive strategies available for doctors when they communicate a diagnosis to patients. To this end, the characteristics of institutional discourse will be taken and the methodology of analysis of institutional discourse proposed by Sorjonen and Drew(2000) will be applied. Once the linguistic particularities in communicating a diagnosis are discovered, we will attempt to apply the conversation framework for breaking bad news in medicine suggested by Buckman(1984, 1992) in order to verify not only the usefulness of that discursive model but also identify the linguistic realizations of each strategy. The results can offer an interesting point of view to understand a linguistic exercise of doctors and its socio-discursive implications.