As a companion to questions about absolute (or perfect) pitch, discussions about if the trait is achievable with training are sure to follow. After these discussions I have read up a bit on the subject, and changed my views somewhat. I thought it would be interesting to have a dedicated discussion, instead of it being spread out in comments.

So, the question is: Can any adult (barring pathological conditions) achieve perfect pitch through training?

(I have searched the existing questions, but couldn't find one with this specific meaning. That pitch perception can be improved is quite clear, the question here is if absolute pitch can be fully obtained in adulthood.)