Xen Matrix™ AB Surgical Graft in Ventral or Incisional Midline Hernias

Inclusion Criteria: * Subject must be willing and able to give written informed consent. * Subject must be diagnosed with a ventral or incisional midline hernia. * Mesh must be placed in the retro-rectus or intraperitoneal plane. * Subject must be willing to undergo open hernia repair and be able to undergo all other study procedures as outlined in this protocol. Exclusion Criteria: * The use of surgical graft as a bridge repair. * The subject has more than 4 prior recurrences. * Subject has a contraindication for the placement of surgical graft. * Complete removal of existing mesh from a prior hernia repair (in the same affected area) is not possible. * The study hernia repair requires more than a single piece mesh (including sufficient overlap beyond margins of the defect on all sides). * Subject has intact permanent mesh adjacent to the current hernia to be repaired. * Subject has peritonitis at the time of surgery. * The subject is an active smoker within the last 2 weeks prior to surgery. * Clinically significant Chronic Obstructive Pulmonary Disease or heart failure, defined as marked limitation in ability or inability to perform activities of daily living. * Subject had chemotherapy within the last 12 months, is on or suspected to be placed on chemotherapy medications during any part of the study. * Chronic steroid use (\>6 months) or immunosuppression drugs. * Subject's body mass index (BMI) \>45 kg/m2. * Subject has cirrhosis, and/or ascites. * Subject has a defined collagen disorder. * Known to be infected with human immunodeficiency virus (HIV). * Subject has clinically significant (not based solely on creatinine levels) kidney disease that limits Activities of Daily Living, is on hemodialysis or peritoneal dialysis. * Subject is American Society of Anesthesiology (ASA) Class 4 or 5. * Subject has a life expectancy \< 2 years at the time of enrollment. * Subject is pregnant, breastfeeding or planning on becoming pregnant during the course of the study. * Subjects with known sensitivity to porcine products. * Subjects with allergy, history of allergy or hypersensitivity to tetracyclines (including minocycline) or rifamycins (including rifampin). * Subject has any condition in the opinion of the Investigator that would preclude the use of the study device, or preclude the subject from completing the follow-up requirements.