The aim of the present review was to critically evaluate the documented evidence regarding the efficacy of biofeedback for the two most prevalent headache conditions--migraine and tension-type headache. Drawing upon two recently published meta-analyses, data from 150 outcome studies, including randomized controlled trials as well as uncontrolled quasi-experimental designs, were screened. Of these, 94 studies were selected for inclusion according to predefined criteria. Meta-analytic integrations were carried out separately for the two conditions of interest. The main results were medium-to-large mean effect sizes for biofeedback in adult migraine and tension-type headache patients. Treatment effects remained stable over an average follow-up period of 14 months, both in completer and intention-to-treat analyses. Headache frequency was the primary outcome variable and showed the largest improvements. Further significant effects were shown for perceived self-efficacy, symptoms of anxiety and depression, and medication consumption. Reduced muscle tension in pain related areas was observed in electromyographic feedback for tension-type headache. Biofeedback was more effective than waiting list and headache monitoring conditions in all cases, while electromyographic feedback for tension-type headache showed additional significant effects over placebo and relaxation therapies. Levels of efficacy (migraine: efficacious, level 4; tension-type headache: efficacious and specific, level 5) and recommendations for future research are provided.