The so-called \'supplementary exercises\' - to be carried out alongside the \'review exercises\' and meditation - are integral to the path of personal development presented by Rudolf Steiner. Together they form a means of experiencing the spiritual realm in full consciousness. Meditation enlivens thinking, the review exercises cultivate the will, whilst the supplementary exercises educate and balance feeling. Conscientiously practised, this path of self-knowledge and development has the effect of opening a source of inner strength and psychological health that soon make themselves felt in daily life. In six stages these exercises enable the practise of qualities that can be summarized as: control of thoughts, initiative of will, equanimity, positivity, open-mindedness and equilibrium of soul. When carried out regularly, they balance possible harmful effects of meditative practice and bring inner certainty and security to the soul. They are also of inestimable value in their own right due to their beneficial and wholesome effect on daily life.In this invaluable small book, the editor has drawn together virtually all Rudolf Steiner\'s statements on the supplementary exercises, supporting them with commentary and notes. With a chapter devoted to each exercise, they are described in detail and from different perspectives.