In April 1987, the TOEFL Research Committee commissioned a project designed to develop a long-range research agenda for the Test of Written English (TWE). The objective of the project was a paper that would outline basic issues in the determination of the validity and reliability of the test. The outline could subsequently be used to motivate and guide researchers in the conceptualization and design of TWE research projects. This paper is the principal product of the project commissioned by the TOEFL Research Committee.