Login in to view posts

I’m setting up a website which will include a blogging and a web publishing component in two separate databases. The blogging bit is fine – I can see how WP will handle that.
But for the web publishing part I am looking for the possibility that people will have to log in to even see the posts. This is because you will have to be a user known to us so as to read the posts, for copyright reasons. My entry page would have to be a customized login page.
Does anyone know a way to do this?