The kinetics of sausage drying were described in terms of a rate equation and of the diffusivity for moisture in a sausage. The rate equation developed is: dx/dt = -k[(x - c)/x]2, where k is the rate constant, t is time, x is percent yield at any time, and c is the ultimate percent yield at t =∞. Data, as percent yield, are substituted into the integrated form of the equation and values for k and c are obtained. The mean square (MS) of deviations of the data from the theoretical curve was used to test agreement. Heating or fermenting the sausages reduced MS and improved agreement. After extended drying, actual percent yields of sausages approximated yields predicted by the rate equation. Estimation of final percent yield, on the basis of sausage weight early in the drying period, should facilitate efficient production and marketing of sausage. By use of equations developed by Sherwood and Newman, the apparent overall diffusivities for moisture in pepperoni were 5.7 × 10−7, 5.6 × 10−7, and 4.7 × 10−7 cm2/sec, respectively, for pepperoni of starting tat content of 13.3, 17.4 and 25.1%.