Moorhouse became Britain's number one breaststroke swimmer in 1981 when he won a bronze medal for the 200 m in the European Championships in Yugoslavia. The following year he gained his first taste of gold after winning the 100 m breaststroke at the Commonwealth Games in Australia, in a new British Record of 1:02.93, along with a bronze in the 200m breaststroke. In the World Championships in Guayaquil shortly afterwards, he missed bronze by just 2/100th of a second in the 100m breaststroke behind (future) 1984 Olympic Champions Steve Lundquist (USA) and Victor Davis (CAN), and future world record holder John Moffet (USA). The following year he was back to winning ways taking gold in the 200m breaststroke at the 1983 European Championships in Rome together with a silver in the 100m.