  The second Red-sequence Cluster Survey (RCS-2) is a ~1000 square degree,
multi-color imaging survey using the square-degree imager, MegaCam, on the
Canada-France-Hawaii Telescope (CFHT). It is designed to detect clusters of
galaxies over the redshift range 0.1<~z<~1. The primary aim is to build a
statistically complete, large (~10^4) sample of clusters, covering a
sufficiently long redshift baseline to be able to place constraints on
cosmological parameters via the evolution of the cluster mass function. Other
main science goals include building a large sample of high surface brightness,
strongly gravitationally-lensed arcs associated with these clusters, and an
unprecedented sample of several tens of thousands of galaxy clusters and
groups, spanning a large range of halo mass, with which to study the properties
and evolution of their member galaxies.
  This paper describes the design of the survey and the methodology for
acquiring, reducing and calibrating the data for the production of
high-precision photometric catalogs. We describe the method for calibrating our
griz imaging data using the colors of the stellar locus and overlapping
Two-Micron All-Sky Survey (2MASS) photometry. This yields an absolute accuracy
of <0.03 mag on any color and ~0.05 mag in the r-band magnitude, verified with
respect to the Sloan Digital Sky Survey (SDSS). RCS-2 reaches average 5 sigma
point source limiting magnitudes of griz = [24.4, 24.3, 23.7, 22.8],
approximately 1-2 magnitudes deeper than the SDSS. Due to the queue-scheduled
nature of the observations, the data are highly uniform and taken in excellent
seeing, mostly FWHM<~0.7" in the r-band. In addition to the main science goals
just described, these data form the basis for a number of other planned and
ongoing projects (including the WiggleZ survey), making RCS-2 an important
next-generation imaging survey. [abridged]
