I haven't done much of this work, but I must say I have found this to be very interesting. It is more than just taking a shot of somebody outside the studio. Environmental portrait is about capturing the image of a person in his own little world, where the background tells a story about the person in it. Thought must be given to creating a strong relationship between the subject and the environment. The environment, in fact, describes the person's personality.
Here is a picture of George. I shot this at the Mont de Lancey outing last Sunday. The lighting was rather dim, so I had to dial up the ISO all the way to 1600. I opened up the aperture as wide as I could ( f4.5). Even then, I could only get to 1/45 sec for shutter speed. It was barely enough for a shot, but I managed to get a fairly decent one after a few attempts. Converted this to B&W, as the theme for our club this month is B&W.