This past fall, while I was assembling my apps, I swapped more than 25 e-mails with a POI. In an e-mail, nestled among his usual philosophical wanderings, was this sentence: "I hope we'll have the opportunity to work together next year." Then he stopped sending me journal articles, and I assumed he got too busy to do the 1-page e-mail trades (which was good for me, too. The guy's really smart, and I'd sweat for hours trying to craft competent responses to his theoretical questions ). We had a good rapport. Nothing weird or awkward happened. But now, since I haven't heard a peep from the program, I'm wondering if it would be appropriate for me to write to him. It's been almost three months since we stopped corresponding. I 'd love to touch base with him, but I'm uncertain of the etiquette rules for this type of thing. Any ideas?