Transection of a peripheral nerve results in a loss of function at the target organ that can rarely be recovered without surgical repair. Such an intervention usually involves nerve autografting but is complicated by problems such as the need for secondary surgery, a limited donor nerve supply and loss of sensitivity in the donor nerve area. An alternative approach involving repair by nerve tubulization has been extensively used to study substances that may improve the regenerative process. An interesting feature of the tubulization technique is the possibility of filling the tube with substances that can enhance regeneration. Such substances include collagen, laminin, hyaluronic acid, fibronectin and, more recently, glycosaminoglycans alone or with collagen. Biopolymers, purified glial cells, and neurotrophic factors have also been tested. By using the tubulization technique, it has been possible to increase the number of regenerating fibers and the gap between the stumps. In this review, we discuss some of the basic concepts of this technique, as well as recent advances in this field.