Reply To: Login
There are various plugins available to will allow you to integrate WordPress login with your active directory.
There are also plugins that will allow you to import users from a CSV file.
And plugins too to add a login widget (we’re using “Sidebar login” on some intranets).
All of my current clients are using inbuilt WordPress accounts and have imported their staff in bulk from a spreadsheet, allowing new staff to register online.
Hope that helps.