Leaders are shaped by institutions and the context in which they emerge. But maybe they are also special personalities. The Hot Politics Lab analyzes these three factors and their interaction to understand leadership in modern democracies. In one paper we analyze how differences in party organizations explain which voters parties follow. We also analyze how the aspirations of political parties influences the degree to which they adopt change. More recently, we have investigated (and found) personality differences between politicians, and the effect it has on their language. For example, we find that liberal politicians use more complex language than conservative politicians, across time and contexts.