Here's another good reason to minimize baggage. I'm not making this up. Another possibility for some trips is two small bags. It snuggles against your colleagues' luggage in a cramped bus, leaving more room for people. It is more practical.
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Do not count on a rolling bag to make up for the fact that you've packed too much stuff. If you don't have the bag you need, hint broadly for such a present if there's a gift-giving holiday between now and your departure. Walk up and down a couple of flights of stairs with everything. Leave a little room in the luggage for stuff you acquire while away. If you're flying, you need an ID on your bag, inside and out.