This paper investigates the efficiency of the Australian stock market during the period of volatility and disruption associated with the Global Financial Crises (GFC). Furthermore, the investigation seeks to observe any divergence in market efficiency between industry sectors that demonstrate differing economic performance across the period. Spanning a time period of 2000–2015, the data are split into three periods of distinct economic conditions: a pre‐crisis period of relatively high growth, the GFC period of disruption and contraction, and a post‐GFC period of relatively low growth. Five sector indices listed on the Australian Securities Exchange are analysed to search for evidence of market efficiency (Real Estate, Consumer Discretionary, Financials, Materials, and Metals and Mining). A range of non‐linear tests are applied in order to systematically investigate the structure of the market in each sector. The results highlight the cointegrated nature of non‐linearity across related sectors, and also demonstrate that different industries within the same economy can reveal highly diverse patterns of non‐linearity and market efficiency in response to financial crisis.