Cognitive behavior therapy (CBT) is recognized as an effective psychological treatment for panic disorder (PD). Despite its efficacy, some clients do not respond optimally to this treatment. Unfortunately, literatures on the prediction, prevention, and management of suboptimal response are not well developed. Considering this lack of empirical guidance, we decided that it would be useful to survey expert cognitive behavioral therapists about what they have found in their practices to contribute to a poor treatment response and what strategies they have found helpful in preventing or managing these problems. Ten factors associated with suboptimal responding emerged. Listed in order of reported frequency, they were as follows: lack of engagement in behavioral experiments, noncompliance, comorbidity, inadequate case formulation/misdiagnosis, secondary gain, problems with cognitive restructuring, presence of other negative life events, medication complications, poor delivery of treatment, and therapeutic relationship barriers. The current paper discusses these factors and details treatment suggestions to improve outcome provided by the survey participants. (Contains 2 tables.)