Many companies face the challenge of building up a data science team from scratch and it can be hard to figure out how to start. In 2016, I was the first hire of a new data science team, with little infrastructure or strategy in place. Over the years, there were many different challenges for us to solve and mistakes to learn from as the team got more and more mature. This talk is about what I learned about the process of building up a data science team, from both my own experience in the past years and conversations with other data scientists in a similar situation.