The report "Business Groups in Euskadi" describes the ownership structure of companies in the Basque Country, highlighting the relevance of business groups. Additionally, it proposes a methodology for the identification and classification of these business groups present in the Basque Country. Thus, the report presents a snapshot of these groups for the year 2022, identifying 4,136 business groups and describing their characteristics based on the location of their parent company, distinguishing between Basque, Spanish (outside the Basque Country), and foreign groups. For each of these typologies, several attributes considered relevant in the literature on business groups are analyzed, such as the sophistication of their strategies, sectoral diversification, and intra-group financing mechanisms. Furthermore, the report provides detailed information on the business groups that generate the most employment in the Basque Country.