This chapter discusses current methods of formative evaluation and suggests that these methods themselves need to be subjected to more critical research and evaluation in order to provide them with a more scientific base. Topics addressed include problems and methods associated with data gathering, evaluation designs, number of subjects available, use of findings, formative evaluation models, decision making algorithms, expert judgments, and the use of data for guiding and improving various stages of the instructional and product development process. (70 references) (Author/EW)