What does it say about someone that accepts adding their name to a publication without doing any of the work? I'm a government researcher in R&amp;D and have spent my career doing and publishing my own work.  Some time ago I was asked to take over some research from another scientist that was being transferred.  She barely started the work and all I ended up receiving were some rough notes for background info - no actual analysis.  I told her that since it was her project at the start, I would add her name to the publication as a co-author.

I have since spent several months doing the research and analysis and am ready to submit the publication.  Since I did promise her to add her name, I did so fully expecting her to tell me to remove it since all the work was really mine - I didn't even use her notes.  All she did was thank me for adding it.

I guess I'm disappointed in her decision to keep her name on the publication.  Is that unethical on her part?
No, it is certainly not unethical. You made an agreement at the beginning and you fulfilled it. She thanked you for your courtesy. All is well. The one, perhaps, contribution that she did make was to get you attached to the project idea, from which you will benefit. You are the primary author, in this case, of course. 

There are many reasons for including someone on a paper and not all are benign, but I think this one is. I assume the other person is quite grateful, and maybe even a bit embarrassed. She may even not want to insult you by asking to be removed, since you had the earlier agreement. 

But judging her ethics will get you nothing but trouble.