The main objective of this post-market surveillance study is to compare the subject's weight loss and quality of life, and device safety performance of the abiliti System and the adjustable gastric banding therapies in obese to morbidly obese subjects.

This study is intended to provide additional data regarding the performance and safety of the abiliti system in comparison to gastric banding. The composite end-point of the study is designed to provide a direct comparison of the effectiveness of the devices for the treatment of obesity while giving consideration to the safety profile for each device and their impact on patient quality of life.

Inclusion Criteria:

• Age of 18 - 60 years old at time of screening
• BMI of 40 to 55 or 35 to 39 with an obesity related comorbid condition at time of screening
• History of obesity ≥5 years
• The subject has been under routine care of the investigator or another single physician that can supply a medical record for at least 6 months prior to enrollment
• Women with childbearing potential (i.e., not post-menopausal or surgically sterilized) must agree to use adequate birth control methods
• No significant weight loss (<5%) within four months prior to enrollment as documented in the subject's medical record.
• Successful psychological evaluation following the institution psychological evaluation protocol for bariatric surgery or successful historic assessment performed no more than 6 months prior to enrollment.
• Glycosylated Hemoglobin; HbA1c ≤ 7.0 % at Visit 2 or historic value performed no more than 3 months prior to enrollment.
• If taking anti-depressant medications, they must be stable for at least six months prior to enrollment
• Willingness to refrain from using prescription, over the counter or herbal weight loss products for the duration of the trial
• Alert, mentally competent, and able to understand and willing to comply with the requirements of the clinical trial, and personally motivated to abide by the requirements and restrictions of the clinical trial
• Able to provide voluntary informed consent

Exclusion Criteria:

• Any prior bariatric surgery
• Other implanted electrical stimulation devices (e.g. pacemaker, defibrillator, neurostimulator)
• Diagnosed with past or current psychiatric condition that may impair his/her ability to comply with the study procedures
• Use of anti-psychotic medications
• Diagnosed with a eating disorder such as bulimia or binge eating
• Obesity due to an endocrinopathy (e.g. Cushing disease)
• Insulin therapy
• GI disease such as hiatal hernia (>5cm), gastroparesis, esophageal motility disorders or intractable constipation.
• Cirrhosis, chronic pancreatitis
• History of intestinal obstruction or adhesive peritonitis
• Any history of peptic ulcer disease within 5 years prior to enrollment
• Women who are pregnant, lactating or anticipate becoming pregnant within 24 months
• Arthritis or other pathologies limiting physical activities that physician feels should exclude the patient from the study.
• Chronic use of aspirin and/or non steroidal anti-inflammatory medications and unwillingness to discontinue use
• Cardiac history that physician feels should exclude the patient from the study.
• Concurrent use of weight loss medications.
• Use of another investigational device or agent in the 30 days prior to enrollment
• A history of life-threatening disease within 5 years prior to enrollment
• Any other condition that, in the opinion of the investigator, would make the subject unsuitable for the study