Second-party data refers to information about customers or prospects, or even external environmental data, provided by a partner to supplement the data already held by a company. This additional data is generally obtained through partnerships, exchanges, or purchases, and can sometimes be considered third-party data. The management and sharing of this data often take place through specific platforms and tools. A specific type of second-party data consists of data collected through collaborations. A concrete example of the use of this complementary data, second-party data, is Danone, which enriches its own data using this approach. A data specialist explains in detail the methodology for collecting this second-party data.