If you are using online TurboTax all she needs is the account and user ID.  If the two of you start entering information --be careful -- make sure the right hand knows what the left hand is doing.

Right, but the account prompts me at my email address when I log in for a security code. Is it possible to add a second account?

No.  The return you are working on is in ONE account with an account and user ID.  Your return cannot be accessed from any other account or user ID.

She'll probably have to call you when she's ready to work on it , so you can tell her the security code.

......In any case, you cannot both have same  tax account actually open at the same time....(if you are trying to do that).  So you can't have it already open when she logs into the same tax account.

Oh--good point!  Right--you cannot both be into the account at the same time.

Using TurboTax Home and Business installed off the CD on 2 computers....how can both myself and wife work on our tax returns on one file but on separate computers....can the files be merged periodically?

@Librarian The only way to do that is to move the data from one computer to the other using a backup device like a flash drive.  Using desktop software is not like using online software.  The data does not just go from one computer to the other.   What you are doing may cause confusion, really.

When you use TurboTax Desktop, your tax file is saved locally on the hard disk of your computer. It cannot be accessed by any other computer (unless the two computers are on the same local area network (LAN).

One solution is to save the tax file (extension: taxxxxx) and to send it by the mail to your wife who can load it on her computer and open it with TurboTax installed on her computer. She can work on it and resend the tax file to you. However, you both have to make sure that you are working on the latest version of the tax file. Both of you cannot make changes to the same file on 2 different computers and merge the 2 files.

This seems like a major design flaw.