The Spastic Paraplegia Foundation, Inc. (SPF) is a national, not-for-profit, voluntary organization incorporated in February, 2002. It is the only organization in the Americas dedicated to Primary Lateral Sclerosis (PLS) and Hereditary Spastic Paraplegia (HSP). SPF is committed to providing information about for these disorders, creating opportunities for mutual support and sharing, and discovering the cures for HSP and PLS by funding research. These closely related upper motor neuron disorders affect some 24,000 children and adults across the United States and Canada. The SPF is dedicated to finding the cures for these conditions and providing information and support services.