During the accomplishment of the first day of the twelfth edition of the International Symposium on Genetics in Aquaculture, and after the inauguration of the event by the authorities (the President of the Symposium Organizing Committee, the Rector of the University of Santiago de Compostela and the Galician Minister of Culture, Education and Universities), attendants had the occasion to receive a retrospective vision of the evolution of the application of genetics to the Spanish aquaculture and of the origins and evolution of this discipline at international level, referring as well to the transfer of knowledge from agriculture and forestry to the most recent applications in the field of the aquaculture. Further sessions along the morning addressed the state of a number of selective breeding programs and the strategies adopted for their development. Among the conclusions stands out the challenge to gain efficiency, especially from the economic perspective, on selection strategies associated to the different cultured species (as there is not the same level of information available for all of them, neither is feasible that this will be obtained); as well as on strategies associated to the traits which are targeted for selection. In addition to more traditional traits (growth and maturation, resistance to illnesses, etc.) increasing importance is given to traits associated to the capacity of adaptation and/or answer of the cultured species to environmental stress factors such as temperature and hypoxia levels, among others. Presentations and further discussions also addressed the different methodological and technological approaches to genetic breeding and the last session of the day was organized as a round table which allowed an active debate about the advantages and disadvantages of breeding based on GBS (Genotyping by sequencing) versus SNP-chips (single nucleotide polymorphisms), addressing both the technical properties and those aspects which have a greater repercussion on industrial uptake, mainly efficiency and cost.