In the last month three book I mailed and two I was expecting never reached destination and were marked as "lost" by PBS.

I never had problems before with packages and mail , domestic or international, so i wonder if madia mail is more likely to be lost.

Has anyone experienced  this problem?

Lost books seem to run in waves Christina.  If you are experiencing an unusually high number, consider discussing the matter with your postmaster.  Sometimes, it's a local or regional problem that can be improved.

Besides possible postal problems, summer months mean PBS members are often very busy, on vacation, or moving...all of which can contribute to lost or misplaced mail.  Have you contacted the other members?  PBS guidelines recommend pm'ing if a book goes lost (or is about to).  Sometimes this will remind the other member to log a book in (or check under the car seat for unmailed books).

I haven't noticed Media Mail being any more prone to loss than other rates, but it could appear that way b/c PBS members frequently use that mail rate.   Since becoming a PBS member, I probably use Media Mail more than all the other rates combined.

I seem to also be having this problem...a few books that were mailed at the end of July have still not come in yet! All other books ordered after that arrived...wondering the same thing you are....hopefully they show up!

so many "lost books" are not the USPS fault at all. the other member doesn't mail it, or forgets to mark it received. The few times one of the books I have sent gets close to being marked lost I send a PM something like this:

Dear -------

I sent your order for "book title and author" on --date--. I sent it in a package that might have been too big for your mailbox. since you havent marked it received yet, could you please check with your local post office to see if they are holding it for you to pick up?

EVERY time i send that PM the book is marked received, usually within a few hours of the PM. They usually say something along the lines of oh, I forgot to mark it received, or I thought I already marked it received. 

I've had a few get lost coming to me. The few that have, I suspect some never got mailed in the first place. I've had a few WL books "sent" to me that are kinda rare. I wonder if they looked it up and saw they could sell it for over face value and went thar route instead.Espesially since I have never gotten a PM asking if I received them.

Thank you very much for your input ,I'm following your suggestions. Hopefully I can successfully locate all these "missing" books.

Has anyone ever had this happen. I sent a package out with four books in it.  When the recipient received it, it only had one book in it.  With the package not opened. Love to hear from someone on this.

Has anyone ever had this happen. I sent a package out with four books in it.  When the recipient received it, it only had one book in it.  With the package not opened. Love to hear from someone on this.

Well, possibly, the package they received was not from you. If they ordered a book, and the first member to receive the order printed the wrapper and mailed, but never marked the book mailed, the order would roll over and you may have sent the second copy of the book to the requester.

Or, if the package is definitely from you, then obviously it was opened. Either it came open accidentally, books fell out, and someone at the PO helpfully sealed it back up, probably not realizing that something was missing. Or, someone at the PO opened it deliberately (although I would rate this scenario as very unlikely, because why would somone risk their job like that?).

Or the receiver is lying.

I have received packages before, where the package ripped or the tape came unsealed, and one or more books was missing, but others reamined in the package and were delivered. I could tell these particular ones had been damaged, but if the PO had repaired the packaging with more tape, I mght not have known that the packaging had been ripped open.

I would also add that if any of your books were coming from or to the east coast during August they will be delayed. They did have an earthquake and a couple of hurricanes during the month. the Northeast especially is not used to it and may have delayed mail.