According to a widely accepted forecast the world reserve of crude oil (known and to be explored) is about 360 Gt. The global oil demand in the 21st century, however, will be roughly 250-260 Gt, thus the recovery factor must be doubled (from 30-35% at present to 65-70% on average) to meet the predicted global demand. Unfortunately, more than 70% of the worldwide oil and gas production comes from depleted reservoirs. Consequently, revitalization of matured oil and gas fields have priority as part of the availability of hydrocarbons. Implementation of novel IOR/EOR technologies, stimulation and optimization of well performance, meanwhile minimizing the environmental impacts, will form the main stream of developments in the coming years and decades. Necessarily, the R+D activity will and must be strengthened in the future putting the oil and gas industry on a new pedestal. The papers in this book intend to demonstrate the recent contributions of research projects to oilfield chemistry, and hence to treasury of advanced production technology.