Book section: The chapter examines perceptions of candidate viability in a series of voting experiments conducted in Lille, Montreal, and Paris. We show that: participants in these experiments are able to distinguish viable and non-viable candidates; these perceptions become clearer over time; and they affect vote choice. Moreover, we show that voters’ behavior is unaffected by whether they are asked (or not) about their perceptions of candidates’ chances of winning. We conclude that, for studying in details the determinants of voters’ choices, there is much to be gained in measuring, in a simple and direct manner, participants’ perceptions in voting experiments.