The aim of the paper is to develop a uniform semantic-pragmatic theory of Controller choice for a numbei of German and English subject control verbs like promise/versprechen and object contiol verbs like request/bitten, recommend/empfehlen, force/zwingen, etc., which prototypically require a complement clause denoting an action performed by a human agent, who is left unexpiessed in the Infinitive clause (PRO). We propose the concept of Semanticpragmatic role* to account for a number of control phenomena which have hitherto been treated äs exceptions. We show that Controller choice and control switch heavily depend on two semanticpragmatic factors, i.e. 'degree of agentivity of PRO9 and 'role identity of a matrix N P and PRO9. Furthermore, at least in English, 'iconicity', i.e. the reflection of referential identity in formal closeness, plays an Import an t role. Our analysis is based on two experiments conducted with 35 native Speakers of German and 28 native Speakers of American English.