We performed a bibliographic review of the systems proposed by various researchers to evaluate physiologic metatarsal protrusion. The system of measurement devised by Hardy and Clapham to evaluate the protrusion between the first and second metatarsals was adapted to study the whole metatarsal parabola. We studied the five metatarsals of 52 normal feet. Mean metatarsal protrusion relative to the second metatarsal was +1.21% for the first metatarsal, −3.84% for the third metatarsal, −9.66% for the fourth metatarsal, and −16.91% for the fifth metatarsal. (J Am Podiatr Med Assoc 96(3): 238–244, 2006)