Three studies examined the impact of a treatment designed to instill resistance to deceptive persuasive messages. Study 1 demonstrated that after the resistance treatment, ads using illegitimate authority-based appeals became less persuasive, and ads using legitimate appeals became more persuasive. In Study 2, this resistance generalized to novel exemplars, persevered over time, and appeared outside of the laboratory context. In Study 3, a procedure that dispelled participants' illusions of invulnerability to deceptive persuasion maximized resistance to such persuasion. Overall, the present studies demonstrate that attempts to confer resistance to appeals will likely be successful to the extent that they install 2 conceptual features: perceived undue manipulative intent of the source of the appeal and perceived personal vulnerability to such manipulation.