The responsibility reading found in tough constructions is also observed in middles and dispositional sentences. This paper argues that the responsibility reading of the tough and middle constructions arises because the two constructions are dispositionals. It will be shown that the responsibility reading is dispositional ascription and it arises because dispositional sentences contain some covert possibility modal force in their meanings. This dispositional approach to tough constructions provides a strong argument for analyses of tough constructions which view the matrix subject as thematic and base-generated in situ.