A novel effort to improve production from carbonate reservoirs has been gaining considerable worldwide interest. The technique involves pumping acid to create new multi-lateral production tunnels. Post treatment production rates have been considerably higher than those seen from bullheaded treatments. The acid is circulated to the formation via coiled tubing and an optimized bottom hole assembly. This presentation will cover the testing, optimization, and operational results realized so far. Case histories from over twenty operations will be presented, together with information on candidate selection. The techniques applicability to the Permian Basin will be discussed.