BACKGROUND: Anxiety disorders are characterised by long term worry, tension, nervousness, fidgeting and symptoms of autonomic system hyperactivity. Meditation is an age-old self regulatory strategy which is gaining more interest in mental health and psychiatry. Meditation can reduce arousal state and may ameliorate anxiety symptoms in various anxiety conditions. OBJECTIVES: To investigate the effectiveness of meditation therapy in treating anxiety disorders SEARCH STRATEGY: Electronic databases searched include CCDANCTR-Studies and CCDANCTR-References, complementary and alternative medicine specific databases, Science Citation Index, Health Services/Technology Assessment Text database, and grey literature databases. Conference proceedings, book chapters and references were checked. Study authors and experts from religious/spiritual organisations were contacted. SELECTION CRITERIA: Types of studies: Randomised controlled trials. TYPES OF PARTICIPANTS: patients with a diagnosis of anxiety disorders, with or without another comorbid psychiatric condition. Types of interventions: concentrative meditation or mindfulness meditation. Comparison conditions: one or combination of 1) pharmacological therapy 2) other psychological treatment 3) other methods of meditation 4) no intervention or waiting list. Types of outcome: 1) improvement in clinical anxiety scale 2) improvement in anxiety level specified by triallists, or global improvement 3) acceptability of treatment, adverse effects 4) dropout. DATA COLLECTION AND ANALYSIS: Data were independently extracted by two reviewers using a pre-designed data collection form. Any disagreements were discussed with a third reviewer, and the authors of the studies were contacted for further information. MAIN RESULTS: Two randomised controlled studies were eligible for inclusion in the review. Both studies were of moderate quality and used active control comparisons (another type of meditation, relaxation, biofeedback). Anti-anxiety drugs were used as standard treatment. The duration of trials ranged from 3 months (12 weeks) to 18 weeks. In one study transcendental meditation showed a reduction in anxiety symptoms and electromyography score comparable with electromyography-biofeedback and relaxation therapy. Another study compared Kundalini Yoga (KY), with Relaxation/Mindfulness Meditation. The Yale-Brown Obsessive Compulsive Scale showed no statistically significant difference between groups. The overall dropout rate in both studies was high (33-44%). Neither study reported on adverse effects of meditation. AUTHORS' CONCLUSIONS: The small number of studies included in this review do not permit any conclusions to be drawn on the effectiveness of meditation therapy for anxiety disorders. Transcendental meditation is comparable with other kinds of relaxation therapies in reducing anxiety, and Kundalini Yoga did not show significant effectiveness in treating obsessive-compulsive disorders compared with Relaxation/Meditation. Drop out rates appear to be high, and adverse effects of meditation have not been reported. More trials are needed.