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Over the past few years, the chemistry community has been mobilized to develop new chemistry that is less hazardous to human health and the environment. This new approach has received extensive attention and goes by many names including Green Chemistry, Environmentally Benign Chemistry, Clean Chemistry, Atom Economy and Benign by Design Chemistry. Under all of these different designations there is a movement toward pursuing chemistry with the knowledge that the consequences of chemistry do not stop with the properties of the target molecule or the efficacy of a particular reagent. One obvious but important point- nothing is benign. All substances and all activity have some impact just by their being. What is being discussed when the term benign by design or environmentally benign chemistry is used is simply an ideal. Striving to make chemistry more benign wherever possible is merely a goal. Much like the goal of "zero defects" that was espoused by the manufacturing sector, benign chemistry is merely a statement of aiming for perfection. While it has already been mentioned that nothing is truly environmentally benign, there are substances that are known to be more toxic to humans and more harmful to the environment than others. By using the extensive data available on human health effects and ecological impacts for a wide variety of individual chemicals and chemical classes, chemists can make informed choices as to which chemicals would be more favourable to use in a particular synthesis or process. Simply stated, Green Chemistry is the use of chemistry techniques and methodologies that reduce or eliminate the use or generation of feedstock, products, by-products, solvents, reagents, etc., that are hazardous to human health or the environment. Green Chemistry is an approach to the synthesis, processing and use of chemicals that reduces risks to humans and the environment. Much innovative chemistry has been developed over the past several years that are effective, efficient and more environmentally benign. These approaches include new synthesis and processes as well as new tools for instructing aspiring chemists how to do chemistry in a more environmentally benign manner. The benefits to industry as well as the environment are all a part of the positive impact that Green Chemistry is having in the chemistry community and in society in general. It is important that chemists develop new Green Chemistry options even on an incremental basis. While all elements of the lifecycle of a new chemical or process may not be environmentally benign, it is nonetheless important to improve those stages where improvements can be made. The next phase of an investigation can then focus on the elements of the lifecycle that are still in need of improvement. Even though a new Green Chemistry methodology does not solve at once every problem associated with the lifecycle of a particular chemical or process, the advances that it does make are nonetheless very important. Green Chemistry that possesses the spirit of sustainable development was booming in the 1990s, and has attracted more and more interest in the 21st century. The study of the organic reactions from the point of view of its greenness must have in mind first of all that a general synthetic method must be based on complete and efficient conversions of well defined selectivity and that greenness is more a term for comparison than an absolute kind of qualification. In order to evaluate the greenness of a particular process attention must be paid in the first instance to issues related to safety, health and protection of the environment, due to reactants (substrates and reagents), auxiliaries (mainly solvents) and waste. This enumeration is obviously incomplete, but can be useful at present. The question about how green a reaction is most frequently refers to a particular conversion, to the comparison between two or more alternative processes for the same synthetic target, or between the synthetic pathways for the manufacture of alternative compounds. The study of the greenness of the organic reaction is completed by a short overview of recent contributions indented to achieve efficient, safe and clean conversions that are susceptible to becoming general synthetic procedures. With the increasing concerns about the environmental protection, synthesis of organic compounds from raw materials through a Green Chemistry procedure is desirable. Certainly the area of environmentally benign solvents has been one of the leading research areas of Green Chemistry with great advances seen in aqueous (biphase) catalysis and the use of supercritical fluids in chemical reactions. While the greenness of ionic liquids and fluorous media will ultimately depend on their individual properties with respect to health and the environment, the sustainability of new biobased solvents has to be proven as well. There has been a renewed focus on the age-old pursuit of the organic chemist to design and successfully apply the ideal synthesis in terms of efficiency, with atom and step economy being a major goal. New catalytic processes continue to emerge to advance the goals of Green Chemistry, while techniques such as microwave and ultrasonic synthesis as well as in situ spectroscopic methods has been used extensively, leading to spectacular results. These research areas are a glimpse of some of the many topics directly relevant to Green Chemistry being pursued by researchers around the world. The development of asymmetric reactions stereoselective formation of C-C bond based on green protocol is also of paramount interest. In recent year�s asymmetric metal, organo-metal catalysis has been intensively studied and several efficient methods for the synthesis of enantiomerically pure compounds have been developed. Our work which is based on green protocol by developing metal and organo-metal promoted synthesis of some organic compounds in aqueous media is also described. This chapter provides background to the present work by reviewing literature on Green Chemistry. The concept of Green Chemistry, its principles and different types of reactions are presented.