A sound knowledge of different facets of petroEconomics is a economics is a sine quo non particularly for the petrochemical sectors dealing with exploration, development, production, refining, transportation. Storage and marketing of oil, natural gas and a wide range of petro products. Evolution and application of the concept of petroeconomics, following the firstever major ‘ oil shock’ in the early 1970s has gained strategic significance and tremendous momentum from the first decade of the 21^st century on the following ground: (i) Emerging need for integration of national energy security with global energy security environment; (ii) Growing concern for safeguarding dwindling strategic oil and natural gas reserves to cater to the growing economy in the developing world (particularly the BRIC nations) with much greater projected future demand for oil and natural gas; (iii) segmentation of the global oil and natural gas market on a geopolitical basis, compounded by the overwhelming ramifications of regional economic unions; (iv) price structuring, rationalization/ parity, and attendant accounting problems of oil and natural gas in terms of upstream, midstream, downstream, marketing/ retailing activities associated with crudes, refined oil and natural gas (including LNG, CNG) products.