For the first time, semiconductor lasers grown entirely by selective area epitaxy are reported. The lasers were formed by in situ processing techniques and metal organic molecular beam epitaxy (MOMBE). A 50 Å thick layer of Si deposited on the InP substrate was used as a mask for both the selective growth and etching. Laser stripes, 6 μm wide, were delineated by a focused Ga-ion beam and transferred into the substrate by Cl2 etching. These steps were performed in the vacuum chambers attached to the MBE machine. Separate confinement heterostructure GaInAsP/InP lasers were grown selectively in the stripes. The resulting devices emit at 1.3 μm and show threshold currents of 40 mA.