To evaluate the use of alcohol- and detergent-preserved tracheal allografts in dogs.Experimental segmental tracheal replacement was performed in 18 adult mongrel dogs. Three different techniques were tried in three groups of dogs. In the first group, a four-ring cervical tracheal segment was dissected out and implanted in the trachea of another dog. In the second group, the procedure was performed using a tracheal allograft that had been preserved in 70% ethyl alcohol for 20 days. In the third group, tracheal grafts were previously impregnated in 10% povidone iodine for 72 h before being implanted. Allografts were harvested 60 days after transplantation and assessed both histologically and in terms of the percentage patency. Dogs that died within 60 days were also included in the analysis.The best results were found in the group in which the tracheal allograft had been preserved in ethyl alcohol and this was explained by the reduced antigenicity of the graft in this group.The use of alcohol-preserved allografts is a practical method of tracheal transplantation, and the alcohol-preservation technique markedly reduces the immunogenicity of the grafts.