The city of Bilbao has made use of a museum as one of the multiple means to restructure its former industrial base. However, the effectiveness of this costly formula is not always clear. Three major issues have arisen: the effects of Guggenheim Museum Bilbao on Bilbao’s image, the effects on overnight stays, and the effects on the local economy. There is little debate about the first issue, and room for more evidence on the second and third issues. The aim is to quantify the museum’s impact on tourism and employment and to calculate its yield (Return on Investment and Net Present Value). The approach adopted is the quantitative analysis of statistical data to try to isolate the economic contribution of the Guggenheim.