Yikes: Technically speaking there should only be 1 global.asa file for a website. Actually however, you can have "nested virtual roots" (refer to: http://support.microsoft.com/kb/173307 for info) that contain their own global.asa files but that can really complicate the entire issue. So, in theory, yes, you can have multiple global.asa files but I would stay away from any site structure like that because of the issues it poses. Question 1) It depends on how you've set up your site (and also how you've defined it in IIS assuming you have admin ability to access the IIS server) but generally your application should be defined as starting from the root folder for that site. Question 2) Unless you know how to set up nested virtual roots then yes, I would put the cart vendor's global.asa file in the site's root and us it from there and factor in your own code you require for the global.asa. Question 3) There's no assurance the global.asa file in the shop directory will be read. Question 4) A single global.asa file should always be placed into the root folder of the site (according to Microsoft). Question 5) You can't, because you can't ensure that the global.asa file in any sub-directory will be run. Question 6) As far as I know, as long as a visitor hits the site either to an HTML file or an ASP file, the global.asa file, if it exists, would be run with the sessionOnStart. So in theory a bookmarked page that is to an HTML file should not matter, i.e. it would trigger the sessionOnStart. Question 7) Guess you're referring to the ApplicationOnEnd event: My own experience with this has been that as long as the server is stopped then restarted. But there can be issues where that might not work requiring a true reboot of the machine. Question 8) Yes, applicationOnEnd does work but I have experienced inconsistencies with it. Question 9) Assuming your cart app does not require a database to store session information, probably your cart application might not work.