Early assessment of problem patient behaviors can be a complex and time-consuming task. These negative behaviors can frequently interrupt and misdirect treatment goals. Most dentists, due to private practice demands, do not have the time and training to assess these behaviors. The emotional stability of each patient is taken for granted. Subtle negative behavioral clues can be detected during medical history taking and the initial patient interview. Current prescription medications can also provide clues concerning past or current treatment for depression, anxiety, psychiatric problems, or substance abuse. The burden of properly assessing behaviors and their impact on dental treatment rests on the dentist's acumen in history taking. All practices have some difficult patients. It is important that dentists recognize patients who have special needs such as those with high anxiety, dependency, depression, obsessional somatic focus, or prior negative dental experiences.