The OLDMISS computer program is used to estimate the ▵V's of vehicles in a collision, when the damage to one of the vehicles is unknown. The program estimates the energy dissipated in the structure of the missing vehicle based on the knowledge of the generic structural characteristics of automobiles, and certain assumptions.OLDMISS has been found to be less accurate for certain impact configurations, especially side impacts. This paper examines the possible sources of errors in the OLDMISS algorithm.This paper also details an alternate algorithm for estimating the energy absorbed by the missing vehicle. This proposed method bypasses the need for estimating the damage profile on the missing vehicle. It also takes into account the presence of induced damage (for side impacts). The new algorithm is validated by reconstructing six vehicle-to-vehicle staged impacts, and twelve RICSAC tests.