  SDSS-V will be an all-sky, multi-epoch spectroscopic survey of over six
million objects. It is designed to decode the history of the Milky Way, trace
the emergence of the chemical elements, reveal the inner workings of stars, and
investigate the origin of planets. It will also create an integral-field
spectroscopic map of the gas in the Galaxy and the Local Group that is 1,000x
larger than the current state of the art and at high enough spatial resolution
to reveal the self-regulation mechanisms of galactic ecosystems. SDSS-V will
pioneer systematic, spectroscopic monitoring across the whole sky, revealing
changes on timescales from 20 minutes to 20 years. The survey will thus track
the flickers, flares, and radical transformations of the most luminous
persistent objects in the universe: massive black holes growing at the centers
of galaxies.
  The scope and flexibility of SDSS-V will be unique among extant and future
spectroscopic surveys: it is all-sky, with matched survey infrastructures in
both hemispheres; it provides near-IR and optical multi-object fiber
spectroscopy that is rapidly reconfigurable to serve high target densities,
targets of opportunity, and time-domain monitoring; and it provides optical,
ultra-wide-field integral field spectroscopy. SDSS-V, with its programs
anticipated to start in 2020, will be well-timed to multiply the scientific
output from major space missions (e.g., TESS, Gaia, eROSITA) and ground-based
projects. SDSS-V builds on the 25-year heritage of SDSS's advances in data
analysis, collaboration infrastructure, and product deliverables. The project
is now refining its science scope, optimizing the survey strategies, and
developing new hardware that builds on the SDSS-IV infrastructure. We present
here an overview of the current state of these developments as we seek to build
our worldwide consortium of institutional and individual members.
