This cumulative doctoral thesis comprises three essays in which "Data Envelopment Analysis"(DEA), an instructive and flexible analytic tool with origins in operations research, is utilized to help clarify three crucial issues that arise when subjecting network industries to price-cap regulation. These issues are: First, the relationship of price-cap regulation with investment, second, the relationship of price-cap regulation with quality and third, the correct cost of capital within price-cap regulation. Without loss of generality, the investigation is focused on the case of electricity. (author's abstract)