I've often wondered about this. I believe that it may depend on the market. I think the idea of bidding early may be a good one, but I've heard several anecdotal tales of people paying too much in advance for hotels in cities I paid very low prices for just a day or two before arrival. Here's my theory on this: I think thereuare may be correct on recommending advance purchases for many areas. However, IF you are wanting to stay in a big city that is a popular convention city, and IF you are planning on staying downtown in a nice hotel that is typically used for convention business, THEN I suspect that later may be better. Here's why I think so: Conventions work by organizations making arrangements directly with hotels or with a city's convention bureau. They schedule the convention center or hotel meeting rooms (depending on size of convention/conference), and make a major deposit. They also are granted a block of rooms at a convention rate. This block is held up until a certain date. Until then, the hotel can't book the rooms for anyone else. Once that date is past, then the rooms become available. If you were to try to book a room well in advance, then the room might not be available. But once the release date has passed, you might get it. In fact, if the conference is undersubscribed, there might be quite a few rooms available at distressed prices. That's the theory, anyway--however, note that rooms are released many weeks in advance, not days, so I'm not talking about the difference between a week before your arrival vs. a day. Another thing I've seen, however, is that for large business meetings (not so often conventions), a company might book a large block of hotel rooms in a major hotel. They pay their deposit. They may end up postponing the meeting and rescheduling it (they can usually rollover their deposit, perhaps with an additional fee, to the new reservation). Their rooms now become available, and if they cancellation was close to the meeting date, the hotel may be more desperate to sell the rooms. I doubt these are factors in many towns and markets, but in large cities and major hotels, I believe they may be a factor. In any case, I tend to book the week of my arrival.