Biologic grafts derive from two basic materials. e rst is human tissue and the second is animal tissue. eir use in hernias is conned primarily to dirty or contaminated elds in which placement of a prosthetic mesh might increase the chance of infection. It is well recognized that primary closure of incisional hernias carries a high recurrence rate and that removal of prosthetic mesh in an infected eld and attempts to primarily close these defects will invariably lead to recur­rence. As a result, enthusiasm has recently grown for the use of biologic grafts that may enhance the repair, decrease the chances of infection, and provide a bridge to a clean wound. If recurrence subsequently develops, it can be managed with a prosthetic material. e biologic grafts have dierent charac­teristics depending on the tissue of origin. Grafts can be based on dermis, either human or porcine, or on submucosa. e dermis-based grafts are prepared in such a way as to allow col­lagen and elastin to remain within the matrix. Although these materials have excellent resistance to infection, they do have the distinct disadvantage of weakening over time because of elastin breakdown. is can lead to eventration, recurrence, or the possibility of pseudorecurrence, which can occur as a result of the weakening of the elastin, increased compli­ance, and softening of the graft. Methods that are utilized to improve the durability of these grafts are the use of glutaral­dehyde and hexamethylene diisocyanate, cross-linking agents which make the material, whether it is human or porcine, more resistant to breakdown by enzymatic degradation. is leads not only to greater durability but also to increasing the susceptibility of these grafts to microbiologic attack. Cross­linking limits the ability of the host to incorporate the graft and make it essentially a part of the native tissue.