Does this happen a lot?  I ordered a book [it was posted for only a short time before I ordered it--like hours] and got back the response that it coudl not be sent because someone on BookMooch had ordered it first.  This struck me as inappropriate, but I am unsure if there is a rule against this.  Aren't we supposed to be sure that we have the books available if we post them?

I have all of my books listed on this site and 2 others.  sometimes it happens that someone orders from each site around the same time.  I honor whichever was requested first.  Some may not like it but I do this because I want my books gone.  Books that have multiple copies here might have not as many there but there is no easy way to check that here other than the reminder list.

that said, when I post a new book I'll post it here first for a few days just in case (unless there are multiple copies).

I belong to bookmooch too. But mostly I use it for unpostable WL books because I can describe them there.  I also have some books posted there that were really common here and not being ordered.  I remove them right away from here when they're ordered. If it's WL or there aren't many posted here than I only post it here.  It's not fair.  If a book is WL over there and not here-than I'll only post it where it's WL.  They probably didn't expect it to be ordered so quickly and at the same time on both sites.

It is frustrating, but when they posted the books, they were available to swap. I am sure that the timing to get orders from both sites at the same time must be infrequent. Since it is a free site and the books do belong to the posters, I don't think PBS can dictate (without losing some members) that books cannot be listed on other sites too.

I cross post on multiple sites too, but I won't post a book on 2 sites in the same day. That's when you have a possibility of it being ordered by 2 people at once.

I post the book here. And if it isn't requested after a few days I'll post it somewhere else.

I also post to multiple sites, and have had the unfortunate situation where a book is requested at two different sites.  Many times the books will languish on both sites for months until something occurs to spur interest in the book, then suddenly everyone wants it.  That happened to me with an Olympics book just recently.

I always post here first, to make certain it isn't a WL'd book before I post to any other site.  And I will honor whichever request comes in first.  So, occasionally, I've had to turn down a PBS member.  (Just as occasionally, I've had to turn down other site's members.)  I try to reduce this possibility by keeping all my Bookshelves up to date, so that no one will order a book from here that I've already promised to someone else there.  But sometimes, the requests are spurred by outside factors, and come in at the same time.  The book(s) in question were legitimately available when posted to this site and available for PBS member to request and they would receive it if they requested it first.

I also have books listed on the site mentioned in this thread.  Please PM me regarding a credit deal.

Deborah

I too post on multiple sites and it just seems to happen sometimes. I hate it when I see the double requests but there isn't anything you can do and I always take the first request.