The Nanga Parbat-Haramosh massif represents a unique exposure of mid-lower continental crust from beneath the Himalayan orogen. Seismic velocity measurements on a suite of quartzofeldspathic gneisses show up to 12.5% velocity anisotropy for compressional waves and up to 21% for shear waves. The degree of anisotropy is a function of mica content and rock fabric strength. Over 30% of the samples have maximum compressional wave velocities of 6.4--6.5 km/s; velocities typically associated with more mafic lithologies. These results have implications for the interpretation of crustal velocity structure obtained from wide-angle seismic surveys where in situ velocity measurements are made from refracted or turning rays that potentially spend a substantial portion of their travel path propagating in the foliation plane. Velocities determined from these surveys may overestimate mean velocities of crustal rocks with well-developed horizontal fabric. In addition, crustal anisotropy due to the development of pervasive rock fabric has the potential to be a significant contributing factor to shear-wave splitting observations. ¿ 2001 American Geophysical Union