Formulas for the theoretical precision of cross-beam winds measured with spaced-antenna profilers are developed and compared with results obtained from simulations for conditions of high signal-to-noise-ratios. These formulas relate the precision of wind measurement to radar and atmospheric parameters. Formulas for Briggs' Full Correlation Analysis, the Intersection method, and the Slope-at-Zero-Lag method are each presented for two implementations-estimating parameters for assumed Gaussian shaped correlation functions, and a direct finite difference method where this assumption is not necessary. For each wind measurement method and implementation, these formulas are used to evaluate, as an example, the theoretical performance of MAPR, NCAR's 915 MHz, Multiple Antenna Profiling Radar. The theory is also compared with the standard error obtained from simulations presented by Kawano et al.  for the MU radar in Shigaraki, Japan. Comparisons show that the Intersection and Briggs' FCA methods are identical and provide the best performance.