Why do indesign add a blank page in a 44 pages booklet when I impose it to print?

Derek,

I've seen your advice and comments here over various queries. You are absolutely right in regards to letting the printer take care of imposition (and trapping). I've learned this sage advice from working at print shops (and for any print designer, it would do a world of good if they did some time in print shop, learning hands on).

One problem we've found is that if a client sends us an imposed file and they've done it wrong, we then have to take the time to print a proof, show the client, ask if this is what they want (100% of the time the answer is no), and then go about getting single page pdfs or spreads and imposing the job at our end. At the outset, the client believes that what they've provided us with is correct and it is not our place to question them. They incur a slight charge for the time and proofing, but in the long run they're not paying for X quantities that are wrong and must be reproduced. There are shops (and online printers) that push the work through and that's what we try to avoid.

Thank you Derek, I wanted to make a model at home with my printer. I will do it from acrobat.