The Modern Interpretation of an Ancient Internal Alchemy Manual "Yellow Court Classic" (or "Jade Writing", as the text refers to itself) is one of the core classic manuscripts of the Taoist cannon. Even though this Third Century text has been extensively used in the Alchemy Practice in China (especially in the Highest Purity school) and referenced in many later classics (such as "The Secret of the Golden Flower", by Lu Dong Bin), the present book presents its first full translation to English. The term "Yellow Court" literary means the central area of the Emperor's Castle, that is open to the Heaven above and connects the Chambers of different Ministries of the Country. Its multifaceted symbolic meaning indicates, in different contexts, center of the body (Dan Tian), spleen as the center of five main viscera (in Traditional Chinese Medicine), a whole human body, or even the overall potentials of the manifestation of the Individual, that includes his or her field of interaction with an environment. This Manuscript provides detailed meditation and visualization instructions, and should be, according to Taoist lore, recited by a practitioner (original Chinese verses, also provided in the current book, sound very melodic) until understood and integrated thoroughly. An adept practitioner would thus develop deep understanding of the own physical and mental functions and abilities to correct and cultivate them to a higher perfection, or according to text: "Dispense thousand troubles and heal hundred diseases, become immune even to fierceness of a tiger and cruelty of wolves and capable to refuse the aging forever". The translation and commentary of the text, developed for the purpose of personal practice, is very contemporary and concentrated on the philosophical understanding and practical use in modern times (commentaries take into account some latest scientific views of the Universe) rather than religious, historical or aesthetic aspects of the work. As the full Chinese version (along with Pinyin and word-by-word English translation) of the ancient manuscript is provided, every reader should be also able to an independent study and discover the benefits according to the own, unique aspirations.