In this article the authors describe a rescue balloon procedure for coil implantation in three cases. In each patient, the coil seemed likely to unravel. The coils stretched when attempts were made to remove the partially implanted but trapped device. The inflation of a nondetachable microballoon in front of the aneurysm orifice allowed the surgeons to complete implantation of the coil and to avoid a more forceful and potentially harmful retrieval. This rescue balloon method may be useful for emergency situations, such as coil stretching with or without migration.