This book contains M. Abed Mazeel's 2011 articles examining several technical problems in the current oil and gas fields and prospects in Iraq. Iraq Oil Ministry has offered twelve areas covering 81,700 square kilometres with the blocks having a mix of oil and gas productivity. However, many blocks contain oil and gas shows and some of them are situated very close to previously discovered fields. The west and southwest of the desert are estimated to have high potential for hydrocarbon, where the own state Oil Exploration Company (OEC) has discovered several fields and many thousand of kilometres of 2D seismic data were acquired. The mentioned regions are thought to contain numerous undrilled prospects and, by that, to be highly prospective. Yet only four exploration wells have been drilled on the blocks, and the seismic coverage is old and of poor quality, including the west and southwest to the south of the country. The potential of discovering high potential reservoirs is very considerable, which may change the Iraqi total reserves to 300 or more billion barrel of oil and 500 trillion bscf of gas. This compilation of articles has the objective to identify and evaluate the petroleum systems of prospects and leads, calculate the reserves and assess the hydrocarbon potential and economics of the twelve blocks, Akkas and Ahdab fields using existing literature and available data published by the Ministry of Oil.