Example systems, methods, and apparatus associated with determining a phase-encoding direction for parallel MRI are described. One example, method includes selecting a set of projection directions along which an MRI apparatus is to apply RF energy to an object to be imaged. The method includes controlling the MRI apparatus to selecting a set of projection directions and to acquire MR signal from the object through a set of detectors. The method includes analyzing the MR signal to identify individual sensitivities for members of the set of detectors and selecting a phase-encoding direction for a pMRI session based on the individual sensitivities for the members. The method produces a concrete, tangible, and useful result by controlling the MRI apparatus to perform the pMRI session based on the selected phase-encoding direction.