The objective of the study is to determine the effects of motivational interviewing (MI), a novel technique of behavioral counseling to promote exercise, on pain and physical function in patients with fibromyalgia (FMS). Patients who met the American College of Rheumatology criteria for FMS and had a visual analog pain score of > or =6 were enrolled in a single group intervention pilot study. Participants received two supervised exercise sessions and an exercise prescription. Thereafter, six exercise-based MI phone calls were made over a 10-week period. Assessments were done at baseline, week 12 (immediate postintervention) and week 30 (follow-up). The primary endpoints were changes from baseline in the fibromyalgia impact questionnaire (FIQ)-pain and physical impairment at week 30. Secondary measures were brief pain inventory (BPI)-pain severity and BPI-pain interference, the number of exercise minutes (NEM) per week, and the arthritis impact measurement scale (AIMS)-depression. The 19 enrolled female participants had a mean age of 52.2 +/- 9.1 years, mean disease duration of 7.5 +/- 5.0 years, and a mean FIQ-pain score of 7.7 +/- 1.4. By week 30, there was significant improvement in both FIQ-pain (-2.6 +/- 2.6, p < 0.001) and FIQ-physical impairment (-1.3 +/- 2.1, p = 0.01). Likewise, BPI-pain severity and pain interference were reduced by -2.4 +/- 2.1 (p < 0.001) and -2.4 +/- 2.0 (p < 0.001), respectively. While the median NEM per week increased from 0 to 32 min (p = 0.001) at week 30, AIMS-depression score was unchanged. In this pilot study, we conclude that telephone-delivered MI to promote exercise was associated with an improvement in patient's level of pain and physical impairment.