I will give a brief overview of redshift surveys for cosmology. The Dark Energy Spectroscopic Instrument (DESI) is the first “Stage 4” experiment, delivering 20 million secure redshifts in its first two years of operations. Public data from DESI’s early data release was made available on June 13, 2023. I will also describe the R&D underway for DESI-2 and a Stage 5 experiment will explore the z > 2 universe fo answer questions about early dark energy and inflation.