Most marketing teams are leaving a lot of money on the table. Brands are collecting an extensive amount of data at various stages of the customer journey. Data science helps us leverage this data into actionable insight that results in a greater return on investment. Data science methods like machine learning, clustering, and regression have moved marketing from a creative domain to a scientific one. By leveraging data science, marketing teams can extend their top-funnel approach to incorporate the full-funnel and uncover product and customer insights at scale in an unprecedented way. To do this, growth marketers should understand what data scientists can and cannot do as well as some of the methods and how marketing teams use data scientists.