The diagnosis and classification of personality disorders have come a long
way since the beginning of the 20th century. Perhaps by this time next cent
ury, the diagnostic manual of mental disorders will be using a dimensional
model of classification that will provide more reliable and meaningful poin
ts of demarcation between normal and abnormal personality functioning. This
article offers suggestions for the form, content, and placement of such a
dimensional model. The particular model emphasized herein is the five-facto
r model of personality functioning, but the optimal diagnostic system will
probably involve an integration of alternative dimensional models.