This article tests for the degree of market power in the Greek food and beverages manufacturing industry over the period 1983–2007 based on the Bresnahan’s conjectural variation model of competition. It also adopts the methodology of Dickson and Yu to estimate the net and the total welfare losses due to the possible existence of market power. The bootstrap method is applied to assign measures of accuracy to the statistical estimates. The empirical results indicate the presence of some degree of market power in the Greek food and beverages manufacturing industry and the existence of welfare losses.