GST law is the single most important structural tax reform in India since independence. This indirect tax reform took almost seventeen years to come to the rule book. Debates and discussions all over the country took place for years and still taking place for its implementation and on its impact. Majority are of the view that the introduction of GST in India will lead to simplification of the tax structure, tax incidence, tax computation and compliance. It will also help in expanding the tax net as well as tax base and increase the revenue to the ex-chequer. In the short-run, though the business operations particularly in MSME sector will be to some extent adversely affeted, it will be of much help in the long-run in reducing the cascading effect and removing the complexity of pre-GST indirect taxes. This book deals with the various concepts and mechanism of GST law. The new topic naturally motivated us to write this book. Various doubts and changes during the implementation stage compelled us to make frequent changes and this book covers not only the basic concept on CGST, IGST, UGST and SGST, but also the changes that took place and the major decisions taken till 24th GST Council Meeting. The book is written in simple language and will help the students and teachers from undergraduate to postgraduate classes as well as the professional students of MBA, MBA (FM), ICAI, ICWAI, ICSI, etc. The book also contains simple illustrations for better understanding of the concepts. Contents: 1. Introduction to Goods and Services Tax (GST). 2. GST Acts (Structure and Terminology). 3. Procedure Relating to Levy of, Collection and Exemption from Tax under GST. 4. Registration, Returns and Assessment. 5. GST Council and Regulatory Framework.