Norwegian enterprises have increased their sales to the oil and gas industry markedly in recent years. In this article, we take a closer look at the petroleum-related turnover of Norwegian enterprises and the effect of a fall in oil prices on turnover. The analysis is based on a survey of enterprises in Norges Bank's regional network. The responses indicate that a share of sales will be affected if oil prices fall below USD 90 and that a drop to USD 70 or lower will have a severe adverse impact on petroleumrelated sales in the Norwegian economy. Overall, the enterprises estimate that they can only compensate for lost petroleum-related sales to a limited extent by increasing sales in other markets in the first one to two years after a fall in oil prices.