The two microcomputer programs are written to estimate the performance of electrostatic precipitators (ESPs): the first, to estimate the electrical conditions for round discharge electrodes in the ESP; and the second, a modification of the EPA/SRI ESP model, to estimate the particle collection efficiency of the ESP operating with the electrical conditions predicted by the first program. Both programs, written in the BASIC computer language, are designed for the IBM-PC and compatible computers and the Tandy 2000 computer. The programs require Advanced BASIC and a color graphics adapter. The models are quite useful and allow rapid assessment of expected ESP performance under a wide variety of conditions. Software description: The program is written in the Basic programming language for implementation on an IBM Tandy, PC, XT, AT 2000, using the PC-DOS (2.0) or higher or the MS-DOS (2.1) or higher operating systems.