The Synthetic Repertory greatly expands upon Kent's. Many new rubrics and remedies have been added. Where Kent's book treats only 591 drugs, this one covers 1,594. The work of many other homoeopathic researchers such as Hahnemann, Knerr, von Boenninghausen, Jahr, Gallavardin, Stauffer, Schmidt, Boericke, Stephenson, Mezger, Allen, Clarke, Julian and Künzli are included. Each remedy and rubric added to Kent's original list bears a superscript to indicate its origin. Thus the reader may judge for himself the validity of any remedy or rubric.