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The current status and performance of the ALPHIE plasma thruster is discussed. This new concept was the subject of two recently granted patents and is radically different from conventional (Kauffman) gridded ion engines. Since it makes use of three DC power supplies and only one electron-emitting cathode disposed outside the plasma chamber, its power processing unit has low requisites. This electron emission is employed for both ionization and neutralization of the ion beam. Contrary to usual ion engines where only ions flow through the grids, in this case ionizing electrons and supersonic ions counterflow through the open spaces of a two-grid system. The performance of this plasma thruster was determined using both laboratory tests and particle-in-cell numerical simulations which confirmed the basic physical principles of the ion acceleration process. Laboratory experiments under realistic conditions show the ALPHIE thruster to produce supersonic Argon plasma flows with peak speeds of 37-44 km/s and therefore specific impulses in the range 3700-4400 s−1 . Additionally, ALPHIE delivers 1-3.5 mN throtteable thrusts using a maximum 325 W peak power, all of which were directly measured in the laboratory. These performances make ALPHIE suitable for station keeping, flight formation and end-of-life disposal of small and medium sized satellites.