Usually called the doctor. Or the caretaker.

Or have gone digital and owns hundreds or thousands of e-books! While I don't know anyone who is down to one shelf, that's mainly because readers aren't so good on pictures; I do know someone who is down to one bookcase, all picture books.

I mention this to be a smartass mainly because e-books are my hope for spending 20 more years in this same house without actually having to get rid of any books I want. We don't yet have a reader we like, but we did just get rid of about 6 shelf-feet or more of records because we have the whole albums downloaded.