The structure of the (√5 x √5)R26.6° reconstruction of LaAlO3 (001) was determined using transmission electron diffraction combined with direct methods. It had a lanthanum oxide termination with one lanthanum vacancy per surface unit cell. Density functional calculations indicate that charge compensation occurred by a fractional number of highly delocalized holes, and that the surface contains no oxygen vacancies and the holes were not filled with hydrogen. The reconstruction could be understood in terms of expulsion of the more electropositive cation from the surface and increased covalency. Surface Reconstruction with a Fractional Hole - (√5x√5)R26.6° LaAlO3 (001). C.H.Lanier, J.M.Rondinelli, B.Deng, R.Kilaas, K.R.Poeppelmeier, L.D.Marks: Physical Review Letters, 2007, 98[8], 086102 (4pp)