Context: The use of sleeve gastrectomy has become the first choice in most severe obesity cases instead of Roux-en-Y gastric bypass due to lower rates of complication. Additionally, sleeve gastrectomy does not involve an intestinal by-pass, and achieves about 70% resection of the vertical stomach. Several studies have found that levels of weight loss following sleeve gastrectomy were comparable to bypass procedures. Aim of work: We will discuss the types of bariatric surgeries, their indication, and complications. We will also try to compare sleeve gastrectomy to gastric bypass. Methodology: We conducted a systematic comprehensive search in literature review using Medline, Pubmed, and Embase from January 1997 to March 2018. We used the search terms: bariatric surgery, sleeve gastrectomy, gastric bypass, complications of bariatric surgery, success rate of bariatric surgery Conclusions: Bariatric surgeries are considered to be the most effective methods in decreasing weight and treating morbid obesity. However, they require high motivation from the individual as they require significant post-operative lifestyle changes in order to achieve satisfactory outcomes. The method of choice in bariatric surgery is laparoscopic Roux-en-Y gastric bypass, especially in extremely obese individuals, as it is associated with best weight loss. Other options include sleeve gastrectomy, which has great outcomes. However, no data is available on its long-term complications and outcomes. More studies should be done to provide a clearer picture of long term outcomes of both kinds of procedures. Keywords: bariatric surgery, sleeve gastrectomy, gastric bypass