Mindfulness-Based Therapies (MBT) are more and more frequently used in the treatment of mental disorders. In the paper the efficacy of meditation programs in the treatment of a variety of mental health problems in diverse adult and adolescent populations and psychological and neurobiological mechanisms underlying these effects were analysed. Intervention studies data supports the efficacy of mindfulness interventions in the treatment of depression, anxiety and addictive disorders. It is proved that mindfulness interventions affect emotion regulation, attention regulation, body awareness and perspective of the self. The effect of mindfulness based interventions in the treatment of mental disorders is supported by scientific rationale of its mechanism of action, and the treatment efficacy data is promising. However, further verification of mindfulness interventions efficacy through a greater number prospective, randomized, controlled clinical research trials is required.