This paper aims to demonstrate the broad impact of demand for goods and services on the Portuguese economy, made by cruise tourists who stop over in the Port of Lisbon. The paper applies the input-output matrix methodology in order to measure both direct and indirect effects on the Portuguese economy. Based on the most updated data available (2016), it is shown that direct demand exerted by cruise tourists in Lisbon, in the total amount of EUR 17,799,011, limited to certain activity sectors, spreads across all sectors of the national economy, by inducing to a dynamic in total national production, reaching EUR 29,329,662 (which can be quantified for each of the 62 activity sectors considered in the input-output matrix).