Originally Posted by
MDSD
We did this, also, and found it an enjoyable day. As wsflyer points out, you don't need formal reservations with Taittinger, but the tour you join may very well be conducted in French - some knowledge of the language will be necessary.
The tour I took of Taittinger was in English--and Chinese. The tour guide did not particularly appreciate that the leader of a Chinese tour group translated everything she said into Chinese: it slowed down her tour a bit, but she gamely adjusted. I believe that English tours are frequent; perhaps you may have to wait a little bit for an English tour (we didn't).
For Pommery, I made reservations online, but they were lost. After politely insisting that we would not wait 90 minutes for the next tour, we received a personal tour. It was very enjoyable. I am just glad I brought the e-mail confirming our reservation. Otherwise, we would have been out of luck.