This paper describes in detail a novel multi-sonar controller developed at the University of Limerick and tested on the new smart, remotely operated vehicle (ROV) Latis at sea in March 2009. The multi-sonar controller allows the simultaneous operation of similarfrequency imaging and mapping sonar by interrogating the sonar returns of the multi-beam sonar in real time and adaptively triggering the pings of each sonar in a terrain-adaptive manner to avoid cross-talk and interference in sonar returns. The technique has benefits in hydrographic mapping and in payload sonar management on unmanned underwater vehicles. Detailed results on the testing of the sonar controller system are reported. The paper also describes the smart ROV Latis, designed and built at the University of Limerick, on which the sonar systems have been tested. With its advanced control systems and high-bandwidth networking capabilities, the ROV Latis is an ideal platform for experimentation of new techniques such as the multi-sonar controller, which can be ported to other ROVs and autonomous underwater vehicle platforms once proven.