Walter Trotta, Global Head of Data Services at Citi Private Bank, presented on the use of graphs in private banking. He defined private banking as an industry that provides full financial services to individuals with a certain range of wealth, which impacts complexity and relationships with clients. The data domain refers to the party entity, including individuals, organizations, or groups of organizations. In private banking, Citigroup faces challenges in managing client relationships, with multiple stakeholders involved, such as spouses, children, grandchildren, lawyers, accountants, family offices, and more. Graph technology was used to solve these problems by creating a graph database that can handle complex queries and relationships between clients, their relationships, and the bank's interactions with them. The presentation highlighted the benefits of using graphs in private banking, including improved data governance, reduced latency, and increased value from data. Key takeaways include the need for fresh thinking, collaboration with business stakeholders, and a focus on business rules and conditions to model graph structures effectively.