The x-ray diffuse scattering from a single crystal of Cu3Au was measured in absolute units in a volume of reciprocal space. The measurement was made while the crystal was held at 703 K (approximately 35 K above the critical temperature for ordering) and the measured intensity was separated into components due to short range order (SRO) and strain. The Warren short range order parameters, pair interaction potentials and the first and second order static atomic displacements were obtained by Fourier inversion of these separated intensities. The relative interatomic pair potentials, out to the third shell, were found to be V2/V 1=-0.5 and V3/V 10 consistent with earlier determinations. The first order atomic pair displacements were found to be contrary to what has previously been assumed: Au-Au first neighbor pairs were found to have negative displacements on average and AuCu pairs positive displacements, compared to the average interatomic distance.