He had been instructed to watch for contact between strangers, particularly any such action that seemed unusual.

The common currency exchanged between strangers was not worth much.

But I'll bet it isn't much different from any meeting between strangers.

But it seemed he spoke only of a casual kiss between strangers.

May also be used between strangers in a non-ironic manner.

This, it should be noted, was not a conversation between strangers.

Finally, I want to make the point that this issue is not the same as the issue of violence between strangers.

As you can see, communication between strangers would likely be different from conversations amongst family members.