The advanced camera for surveys (ACS), scheduled for installation on the HST observatory in December 1999, is nearing completion at Ball Aerospace. This versatile camera, comprising 3 detector systems covering the wavelength range from the far UV through 1.1 micron, a large complement of filters, polarizers, prism and grism dispersers and a coronagraph, must be fully characterized before launch. We present plans for the instrument-level optical performance verification and calibration which will be performed later this year. Our intent is to perform a comprehensive characterization of the ACS to facilitate plans for its use aborad HST and to optimize the scientific usefulness of the immense data volume that ACS will provide. In order to comply with the aggressive delivery schedule and relatively restrictive budget, the calibration program will make use of much of the tools and apparatus developed at Ball for previous HST instruments and the data acquisition process will be improved, applying the lessons learned from those earlier programs.