An accurate and efficient tool for the design of contoured beam reflectarrays is presented. It is based on the Spectral Domain Method of Moments, the Local Periodicity approach, and a minimax optimization algorithm. Contrary to the conventional phase-only optimization techniques, the geometrical parameters of the array elements are directly optimized to fulfill the far-field requirements. The design tool can be used to optimize reflectarrays based on a regular grid as well as an irregular grid. Both coand cross-polar radiation can be optimized for multiple frequencies, polarizations, and feed illuminations. Two offset contoured beam reflectarrays that radiate a highgain beam on an European coverage have been designed, manufactured, and measured at the DTU-ESA Spherical Near-Field Antenna Test Facility. An excellent agreement is obtained for the simulated and measured patterns. To show the design tool’s ability to optimize electrically large reflectarrays, a 50 × 50 square wavelengths contoured beam reflectarray has been designed.