The BHP Billiton Cannington mine uses sequential flotation to treat a silver, lead and zinc ore supplied from an underground mine. The final products from the process plant are a silver rich lead concentrate and a zinc concentrate. Operational history of plant performance highlighted that the majority of valuable metal losses to final tailing occurred in the -5 m fraction. Research completed on the flotation characteristics of this size fraction in plant feed resulted in the development of a split flotation process to improve the silver and lead mineral recoveries. Construction of a $A 9.5 million brownfield project to install the new split flotation circuit at Cannington was completed in July 2002. The circuit consists of three stages of cyclone classification to recover the ultra fine material to a final cyclone overflow stream, conditioning of this pulp to achieve optimal process conditions, and conventional rougher and three stage cleaner flotation to produce a silver rich lead concentrate. The rougher tail from the new circuit is recombined with the cyclone underflow streams and processed through the original lead-zinc flotation circuit. This paper discusses the circuit design, material properties, material selection for components of the circuit, operational practices and requirements to ensure the circuit succeeded in meeting production targets. The technology is subject of a number of patent applications including international application No PCT/AU02/00400.