In the latest time electromagnetic boundary layer control can be considered as an actual problem again. Therefore it is worth remembering on some basic ideas which correspond to the previous waves of interest. If in the boundary layer a Blasius velocity profile is replaced by an exponential one its stability is essentially increasing. Already in 1961 we proposed to introduce this fundamental statement in theory of electromagnetic boundary layer control - to apply to the liquid with exponentially distributed e.m. forces and keep the thickness of the boundary layer below its critical value. These forces are determining a propulsing action and up to velocities of practical interest the corresponding energetical balance can be kept positive. Critical values for thickness of exponential boundary layer were taken from traditional linear theory of stability. To ensure an exponential profile it was proposed to cover the surface with a regular array of striplike magnetic poles separated by electrodes of the same width. It was clear that at such an arrangement the distributions become exponential only starting with a definite distance from the surface. To underline the importance of this circumstance corresponding calculations were undertaken. The main idea that boundary layer can be essentially influenced by e.m. forces was confirmed experimentally. A 1.5 m long plate covered with the mentioned array of magnetic poles and electrodes was investigated in a roundabout rotating channel with electrolyte. In an other small scale experiment the forces were localized in the boundary layer in a following way. A D=2 cm cylinder was placed in a channel with pure water. Only the boundary layer was made conductive by means of injection of electrolyte. The magnetic field was directed perpendicular to the surface of the cylinder but the electric current between two electrodes was passing along its generating line.