Is there such a thing as an obligation to trust? It seems a peculiar kind of obligation, if it exists. Suppose that although my fiancée has always been faithful, on the night before our wedding I endeavor to test her fidelity. To this end, I hire an attractive man who attempts to seduce her in private. My fiancée rebuffs the man, at which point I present myself to her and happily explain that she has passed the test. I think most would say that my fiancée would be rightfully indignant in this case, that I have wronged her somehow. Does this show that I violated an obligation to trust my fiancée? Is that obligation contingent on her history of fidelity (such that a history of cheating might justify the test)? Perhaps we can explain the wrongdoing without reference to trust--by way of a prohibition on manipulating or deceiving others, say. Or perhaps no wrong committed here at all.