I just back from my very first Seabourn cruise on the Odyssey to Alaska, and I was extremely worried that I wouldn't fit in.at all. I'm very laid back, more middle than upper class, and while I do like to dress up nicely in the evening, during the day I like to be comfortably casual. I was more than pleasantly surprised to see that I had absolutely nothing to be worried about. I met the nicest, most friendly group of passengers and the crew were hands down the best crew I've ever come across on a cruise. We did dress up on formal night, with my BF wearing a tux and me wearing an evening gown, but not everyone was dressed like that. For our dinner at the TK Grill, my BF did not wear a jacket and the hostess even made it a point to tell us it wasn't required when we were making our reservation. Many of the men we saw weren't wearing one either. As for dinner in The Restaurant, most men didn't wear jackets there either. Maybe it was because it was a more relaxed environment being a cruise to Alaska or maybe it's because they just didn't feel like packing them. My BF wore exactly what your husband wears (collared shirt and nice pants) and he fit right in with everyone else. The moral of the story is that I worried for nothing and we had the most amazing time.