Echolocation call parameters of six species of rhinolophid and hipposiderid bat species occurring in Swaziland are presented. All calls were obtained with the frequency-division ANABAT bat detector, and mostly from hand-held individuals. There did not appear to be any differences in calls between hand-held and free-flying bats. However, there were significant inter-specific differences with respect to the constant frequency component of the call (equivalent to maximum frequency) and call duration. Minimum frequency was found to be highly variable, and considered not useful for species identification of free-flying individuals. Call parameters obtained in this study are very similar to those obtained with the time-expansion Pettersson detector, suggesting that for this group, choice of detector makes little difference. It is suggested that bat detectors provide an important method to inventory southern African bats, and supplement traditional, capture-based techniques, notably mist nets and harp traps.