Paris museum pass

No it is limited to one entry for all museums; this is a new policy. You also need a reservation to use it at the Louvre; people are being turned away who show up with the pass.

Is there a reason not to get the Paris Museum Pass ahead of time before you go at booking.parisinfo.com ?

@jaaldag, I would rephrase your question as "is there any reason TO get the Paris Museum Pass ahead of time ?" Can be done in minutes after you arrive, with no shipping charges and no wondering whether the package will arrive in time.

Some question as to whether one can make Louvre timed reservations without a physical museum pass in hand -- sounds like that process is still being developed.

EDIT -- Another post says the pass number IS needed to book free Louvre reservations. One poster's suggestion was to pre-book a timed Louvre reservation online (€17) if the Louvre is important to you, and get a museum pass when you get to Paris as needed (the other museums don't currently require timed reservations with the pass.)