Title: Arrow's theorem and strategy-proofness. A nonstandard approach Abstract: The well-known theorem of Arrow states that if a social choice rule satisfies certain natural properties then the corresponding voting mechanism is dictatorial. This fact is often used to illustrate the limits of democracy. A closely related result is the one by Gibbard and Satterthwaite showing that nonmanipulable voting mechanisms (with more than two real alternatives) must also be dictatorial. A standard proof is a reduction to Arrow's theorem.