This paper constructs and analyses the properties of a trimmed mean inflation rate for South Africa. Based on an analysis of the distributions of the consumer price index component price changes, a measure is constructed that provides an estimator of core inflation, which may be particularly useful to policymakers in an inflation-targeting environment. The trimmed mean estimator focuses on the price movements of individual components that have a strong bearing on the current and future trend of the headline inflation rate, allowing monetary policy to be directed at the persistent or underlying sources of inflationary pressures. Copyright (c) 2009 The Authors. Journal compilation (c) 2009 Economic Society of South Africa.