BigDat 2023 Summer is a high-level specialized training event dealing with massive data (or ‘big data’). This field covers a vast area of research and innovation with an extraordinary potential impact on scientific discoveries, health, engineering, business models and society itself. Sub-areas of work such as fundamentals, infrastructure, administration, search and mining, analysis, security and privacy will be presented, as well as applications to biology and medicine, business, finance, transportation, social networks, etc. It is the seventh edition. The previous ones took place in other places in Spain, Italy, Romania and the United Kingdom.