Presented herein are studies of the steady-state beat-transfer phenomena in an aligned flow past a semi-infinite flat plate in which the flow velocity and magnetic field vectors far from the plate are parallel. A viscous, electrically conducting, incompressible fluid is used as the working medium. For simplicity, the physical properties are assumed constant and the electric field is taken to be zero. It is found that increasing the magnetic field increases the viscous, magnetic, and thermal boundary-layer thicknesses. The rate of heat transfer, however, is decreased with increasing magnetic field for Eckert number Ek ≥ 0; while for Ek > 0, the opposite trend of heat-transfer rate is observed. Furthermore, for Ek ≤ 0, the rate of heat transfer is higher at a larger Prandtl number; while for Ek > 0, lower values of Prandtl number render higher heat-transfer rates. The predicted heat-transfer results are outlined in this analysis. © 1968.