Abstract.According to Jackendoff (1987b, 1990) conceptual structure consists of, at least, two tiers: the thematic tier (roles Agent (i.e. causer), Theme, Location, Goal, Source, Route) and the action tier (the roles Actor, Undergoer, Patient, and Beneficiary). This paper discusses the assignment of the action tier roles. The theory proposed in this paper abandons the lexical indexing and suggests that action tier role assignment is based on free principles. In Jackendoff's theory (1990) argument linking is primarily based on the action tier and only secondarily on the thematic tier (cf. Foley&Van Valin 1984). According to the present investigation the action tier cannot have any major role in argument linking.