The equations describing pressure decay in the transient pulse method for measuring permeability and specific storage have been used to obtain error estimates. Experiment design is aided by using the sensitivity coefficients of pressure with respect to the two physical parameters. Permeability is relatively insensitive to the ratio of sample storage to upper reservoir storage, but specific storage becomes more sensitive as this ratio increases. Permeability is measured, in general, significantly more accurately than specific storage by the pulse decay method.