Local positioning systems (LPSs) based on acoustic transducers (mainly ultrasonic) offer accurate localization in indoor environments. However, their performance is commonly limited by the transducers' frequency bandwidth and emission pattern. 3D-LOCUS is a new advanced acoustic LPS that claims subcentimeter accuracy even in turbulent environments. This is achieved through the use of broadband omnidirectional transducers, suitable design of emitted signals, proper calibration, and bidirectional emissions. This paper evaluates the 3D-LOCUS LPS by providing results in terms of some positioning metrics such as accuracy, resolution, and coverage, which show how it outperforms other state-of-the-art LPS prototypes. 3D-LOCUS operating in bidirectional mode minimizes environmental effects, such as temperature and airflows, attaining localization errors below 9 mm with a 90% confidence level, an RMS error below 7.4 mm, and 5 mm resolution in a localization volume of 2 times 2 times 0.4 m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> .