The net force on a charge due to multiple other charges equals the vector sum of the individual Coulomb forces: $F_{net}$ = $F_1$ + $F_2$ + ... + $F_n$. Each force is calculated independently as if the other charges don't exist. This principle applies equally to electric fields: $E_{net}$ = $E_1$ + $E_2$ + ... + $E_n$. Superposition is exact — there are no correction terms for three-body effects. When applying superposition, always resolve forces into components (x, y, z), add components separately, then find the magnitude and direction of the resultant. For symmetric configurations (charges at polygon vertices), exploit symmetry to reduce computation — opposite contributions often cancel.