I present a novel way to think about promising: Promising as Doxastic Entrustment. The main idea is that promising is inviting another to entrust her belief to you, and that taking a promiser’s word is freely choosing to accept this invitation. I explicate this through considering the special kind of reason for belief issued by a promiser: a reason whose rational status depends both on the will of the promiser to provide it, and on the will of the promisee to (...) accept it. Though this may seem to raise worries about believing at will, I show how such concerns can be navigated. I then argue that the view provides a rich, attractive understanding of the interpersonal bond forged through promising. According to the Doxastic Entrustment view, that bond results from freely given trust, in exchange for freely assumed responsibility for what is entrusted: namely, a bit of the promisee’s own mind. (shrink)