%0 Journal Article %T On the amenability of partial and enveloping actions %A Fernando Abadie %A Laura Mart¨ª P¨¦rez %J Mathematics %D 2009 %I arXiv %X We prove that a partial action is amenable if and only if so is its Morita enveloping action. As applications we prove that any partial representation of a discrete group is positive definite, and we extend a result of Zeller-Meier concerning the amenability of discrete groups and the existence of invariant states to partial actions. %U http://arxiv.org/abs/0906.1562v1