Communication in a virtual office must be precise or the office will get off task. One of the main factors in determining communication success is the richness of the channel used. Richness is basically the amount of interaction between the communicators. A face to face meeting is very rich while a letter mailed through the post is very low. In a rich medium questions and answers can be used to come to a shared understanding.
Workers have to have a shared understanding of their work to do it effectively.
I leave Mr. Tyson notes in his mailbox at the swim center. These notes give short simple messages that often have to be expanded on. I only leave notes when I know he will pass the box some time during the day. When I do not know if he is gonna pass the mailbox I send him an e-mail. In these e-mails I usually try and lay out road maps of where I am heading and what I have done.