A new closure technique developed for lateral thoracotomy approaches in emergency surgeries was used to close 20 thoracotomies in 5 cats and 15 dogs, and the results were compared retrospectively to a previously recommended and published technique. The continuous shoe-lace technique involved the use of monofilament 2–0 (cats) to 2 sized (large dogs) polypropylene on a swaged on taper needle. The closure pattern began at the dorsal aspect of the intercostal opening just caudal to the caudal rib and then moved to just cranial to the cranial rib. The pattern continued in a continuous fashion, placing a suture bite every 1–2 cm (cats) to every 3–4 cm (large dogs). At the ventral aspect of the incision, the closure continued back dorsally with a continuous lacing-like pattern. At the conclusion of the pattern dorsally the sutures on each side of the incision were pulled tight. The opening between the ribs was brought together with this tightening. The single knot was then tied. Results revealed a more rapid closure than the conventional closure (averaging 10 minutes versus 20 minutes, respectively). No dehiscence was observed with either technique. The single knot was able to be tied without any difficulty. No other complications were observed. This study proved that the new closure technique was very effective. It is recommended over the routine previously accepted and published method because of increased speed and less suture material buried. This is especially helpful in emergency surgery where surgery time needs to be as short as possible.