If you set up two user account in Windows on the PC then iTunes will set up a different library and setting for each user (provided they are logged into their own account in Windows). This is the best way to keep two user accounts completely separate on the same PC. When using a single library for two accounts, I'm no longer certain how iTunes will react. In the past it's been a problem. Not huge uncorrectable problems, but apps and content tended to get mixed up and on the wrong devices, causing problems with updates and downloads on those devices. For people who typically have two country accounts (for access to content they can't get in their own country) it's a way of life. So, yes it can be done and survived, but I don't really recommend it for two people, as there will 'probably' be some constant low level confusion as to which app was purchased with which account. If you still want to share content, but not the same personal data like email, contacts, calendars, etc, then you can keep the same Apple ID on each device for the iStores, but get a separate Apple ID for iCloud. This also gives you each 5GB of free iCloud data for your backups, instead of having to share. Using your Apple ID for Apple services If these aren't the options you are looking for, please provide more details on what you need/want to accomplish.