Veto power consists of the right of one or more players to unilaterally block decisions but without the ability to unilaterally secure their preferred outcome. Our experiment shows that (i) committees with a veto player take longer to reach decisions (are less efficient) and generate less consensus than without a veto player, (ii) veto power substantially enhances proposer's power, and (iii) non-veto players are substantially more willing to compromise than veto players. We relate our results to the theoretical literature on the impact of veto power as well as to concerns about the impact of veto power in real-life committees. © Economic Science Association 2010.