Abstract
Above and beyond the inflow performance of the oil and gas reservoirs, the drilling, completion, and hydraulic fracturing technology has a major influence on the production capacity of oil and gas wells. The performance of a perforated completion is dependent on the nature of drilling and perforating operations. Formation permeability is reduced by invading fluid (both drilling and completion) and by the perforating process. When a well is not producing as expected, the formation may have low permeability or/and may be damaged, or nonflow Darcy effects. If the evaluation of the well productivity during the Drill Steam Test or drawdown tests and the production of other wells in the same reservoir show that the production of the examined well should be higher, then we can look for the reason for the low production. When the restricted flow into the wellbore caused by the improper well drilling or well completion technology then the near wellbore damage should be removed or decreased, and the completion technology should be corrected. In order to increase the efficiency of well performance and select the right well stimulation method it is necessary to recognize the reason for the low production. After recognizing the source of low production we will be able to increase the well production by selecting and applying the suitable well stimulation method and it is possible to correct the drilling and completion technology in other to increase the production of the wells that will be drilled in the future.