On 14 October 2021 Ana Mencher defended her thesis conducted in the MicroWine group of the ICVV, under the supervision of Ramon Gonzalez, Pilar Morales and Jordi Tronchoni. In her thesis, Ana Mencher studied the mechanisms of interaction between different yeasts of oenological interest. The approach of the thesis responds to one of the recent trends in oenological biotechnology; specifically, the development and use of yeast starter cultures other than the traditional Saccharomyces cerevisiae. However, these new starter cultures must normally be used in combination with S. cerevisiae to ensure that fermentations are successful. The study of the interactions between these different yeast species has academic interest, as it is an aspect that has been poorly studied and has the potential to provide new insights in microbial ecology. But it also has great potential to contribute to the design of yeast combinations suitable for each oenological objective, as well as the utilisation conditions. The results of the PhD thesis include the description of the impact on S. cerevisiae gene transcription of the presence of other, potentially competing yeasts. This response shows some common aspects and other more specific ones, depending on the species with which it interacts. The description of extracellular vesicles as potential participants in the communication between different oenological yeast species is also very relevant and novel. Finally, it can be highlighted that Ana's thesis shows how the protein content of the extracellular vesicles of five yeast species analysed is also differentially modulated by the interaction with other oenological species.