A three-dimensional model of the scattering of VLF waves in the Earth-ionosphere waveguide by localized disturbances in the lower ionosphere is examined for typical disturbances expected to be produced by lightning-induced electron precipitation events. Results indicate that the scattering is generally independent of the conductivity and permittivity of the Earth's surface immediately beneath the disturbed region except for extremely low conductivities such as that found over deep ice caps. Thus the scattered signal is principally a function of the ionospheric perturbation. For typical disturbances characterized by altitude profiles of enhanced ionization expected for 1.4≤L≤3, most of the measurable wave energy scatters within a fairly narrow angular region (15-dB beam width of ¿7¿ for a disturbance radius of 100 km) centered on the forward scatter direction. Thus moderate- to -large-scale disturbances (radius 50--200 km) must be located within <250 km of a moderate-length path (3000--16,000 km) in order to scatter a measurable signal to the receiver. These two findings suggest that the scattered signals can be used with confidence as a diagnostic tool to determine the characteristics of the energetic electron precipitation. ¿ American Geophysical Union 1993