on all the steps involved in rendering something in numeric form. Controversies are public disputes about a quantification. Relevance means that number makes a difference, affecting how political issues are interpreted and handled. Finally, numbers are objective when they are taken for granted, when the production process of quantification fades from view. It is often argued that such objectivity is made. Numbers never arrive from nowhere but are produced by someone according to some procedure. Work needs to be done for quantitative information to appear as objective information. When objectivity-making succeeds, however, numbers become politically relevant due to the political attractiveness of seemingly neutral descriptions. The politically relevant numbers are those that appear objective, whereas controversial numbers make less of a political difference. This, however, only captures one aspect of the politics of numbers. Politics is about dissent, contestation and conflict, and quantification does not succeed only when it manages to suppress or supersede conflictual politics. To get at this, the thesis explores a number of dynamics between relevance and controversiality. The first is controversial relevance. When something matters, it matters in a way that some will contest. In many contexts, numbers will do political work in spite of critique and controversiality. Controversies cannot be eliminated but if they can be managed, they do not preclude relevance. Secondly, the importance of avoiding controversiality sometimes causes relevance to be traded away in managed irrelevance, where politically relevant use of numbers is eschewed in order to evade critique. Finally, controversies can enable relevance. Because quantification is an authoritative form of information, arguing that something should be quantified signals seriousness about addressing it, opposing the quantifier to those who want to ‘ignore’ the issue by leaving it unmeasured. In this case, debate and contestation about numbers will underline the politically relevant difference between quantification opponents and proponents. A dynamic I term relevant controversiality. The politics of numbers is not always a politics of objectivity. There are limits to objectivity.