Ding! Ding! Ding! Yes, Victor, that is the standard/canonical solution. But I'd be interested if there are any solutions involving sending keys inside of locked boxes. (I don't know if there are any, but it would be interesting if there were.) At 11:30 AM 5/9/2016, Victor Miller wrote:

Is the following within the rules?

1) Man sends box containing ring, padlocked to the lady. 2) Lady adds her own padlock to the box and sends it to the man. 3) Man removes his padlock with his key and sends the locked box back to the lady. 4) Lady uses her own key to remove the her padlock. No keys are exchanged.

On Mon, May 9, 2016 at 2:18 PM, Dave Dyer <ddyer@real-me.net> wrote:

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At 10:49 AM 5/9/2016, Brent Meeker wrote:

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Send the key first. Only send the box after the key arrives.

No, send the box first. If an anonymous locked box won't get through, the whole exercise is pointless. Any attempt to send the key first might alert the authorities to watch for the box. Once the box is safely transferred, as many attempts as necessary can be made to send a key for the box, which is already secure.