Since the discovery of III-V oxidation by Dallesasse and Holonyak in 1989, significant progress has been made, both technically and commercially, on the use of oxides in compound semiconductor devices. The process-induced modification of refractive index and conductivity allows control of the two carriers of information in optoelectronic systems, the photon and the electron, enabling wide-ranging device applications. Of great technical and commercial importance has been the use of oxidation for the fabrication of high-speed vertical-cavity surface-emitting lasers (VCSELs), first implemented by Deppe's group at The University of Texas at Austin (Austin, TX, USA). Here, the low refractive index III-V oxide's interaction with the optical modes inside the VCSEL creates an optimal overlap of gain and field, enabling lasers with ultralow threshold currents and desirable optical beam properties. The discovery of III-V oxidation, key technical milestones in the fabrication of photonic and electronic devices that use oxidation, and the application to VCSELs are reviewed.