I'd like to know the answer to this one as well.....

Yes, there is a ticket at the price of 12 Euro, that allows access to the following :

Acropolis of Athens,Ancient Agora and Museum, Areios Pagos, Keramikos and Keramikos Museum, Hadrian Library, Roman Agora and
Olympieion ( Temple of Olympian Zeus), North and South slope of the Acropolis.

The ticket cannot be purchased on line, only on the spot.

The entrance to the New Acropolis Museum is not included in that ticket, and must be purchased separately.
Entrance costs 5 Euro, and this ticket can be purchased online at: www.theacropolismuseum.gr

The ticket you mention is the regular entrance ticket to the Acropolis. It covers the other locations, so don't throw it away. It is also good for several days. If you want to visit some of the other locations but not the Acropolis, you buy individual tickets. As far as I know, you can only buy tickets on site. You can buy Acropolis Museum tickets online though.

Worth noting that if you visit one of the sites other than the Acropolis first you have a choice to buy the individual ticket for that site, or the combined one as Clausar detailed above. Always opt for the combined ticket if you are going to visit the Acropolis later(a given for most people!)because as stated you have to buy that one there anyway if you haven't already got it.

Great! Thanks for the helpful tips everyone

How many days is the multi-ticket good for?

Is there a distinction between The Acropolis of Athens and the North/South slopes of the Acropolis as articulated by Clauser?

Assuming the line at the Acropolis is the longest or one of the longer ones, is there one site amongst those mentioned that it is easier to purchase the ticket?

What is the impact of a potential strike at one or all the sites, if that is even possible, do the days of the ticket extend past a strike or are they consumed by it?

Much obliged...bdj

I've never waited more than a few minutes for tickets on location and I am there in June and July - a busy time.
I also recommend the multi-site ticket.

In Athens as almost anywhere in Europe simply get there at opening time and you'll not only have little if any wait but you'll get to see the place without the mobs before the tour buses start arriving...

Would anyone know if there is a specific website that defines the parameters of the multi-site ticket? Days available? Etc?

Much obliged...bdj

The Greek Ministry of Culture has a fabulous portal that provides information on all archaeological sites, monuments, museums etc of Greece.

Please visit : http://odysseus.culture.gr/h/3/eh30.jsp

As for the Acropolis ticket, it is valid for 4 days.

clausar...Thanks for the link and the info, both invaluable in planning the trip.