We reported earlier that preincisional paravertebral block (PVB) provides significant immediate postoperative analgesia after breast cancer surgery. In the same patients (n = 60), a 1-yr follow-up was performed to find out whether PVB could also reduce the prevalence of postoperative chronic pain. The follow-up consisted of a 14-day symptom diary and telephone interviews 1, 6, and 12 mo after surgery. The 14-day consumption of analgesics was similar in the 30 PVB and the 30 control patients. However, 1 mo after surgery, the intensity of motion-related pain was lower (P = 0.005) in the PVB group. Six months after surgery, the prevalence of any pain symptoms (P = 0.029) was lower in the PVB group. Finally, at 12 mo after surgery, in addition to the prevalence of pain symptoms (P = 0.003) and the intensity of motion-related pain (P = 0.003), the intensity of pain at rest (P = 0.011) was lower in the PVB group. These findings were independent of whether or not axillary dissection had been performed. The incidence of neuropathic pain was low (two and three patients in the PVB and control groups, respectively). In addition to providing acute postoperative pain relief, preoperative PVB seems to reduce the prevalence of chronic pain 1 yr after breast cancer surgery.