Fluorescence localization microscopy techniques such as PALM and STORM achieve super-resolution by sequentially imaging sparse subsets of fluorophores, which are localized by means of Gaussian-based localization. Applied to fixed fluorophores, with dipole radiation characteristics, this can lead to an estimation bias in the range of 5-20nm. We introduce a method for the joint estimation of position and orientation of single fluorophores, based on an accurate image formation model expressed as a 3-D steerable filter. In addition to avoiding bias in PALM/STORM, it can remove the ambiguity of the orientation factor for studying dipole-dipole interactions at the single-molecule level.