This chapter draws on Herbert Blumer's (1969) essay "The Methodological Position of Symbolic Interactionism". In this essay Blumer clearly establishes the role of theory in the selection and development of measurement techniques. The act of measurement assumes that observations of concepts may be transformed into statements concerning the degree to which they are present in a given empirical instance. Scales may be distinguished by their level of measurement. In several senses the logic of open-ended measurement strategies reflects a commitment to the delayed operationalization position. Index construction is one strategy of triangulation, then. While confined to the measurement level, the assessment of indices internally and against outside variables represents a technique for combining different measures in the analysis of the same empirical event. It can be argued, that all data, whether qualitative, or quantitative, serve four basic functions for theory. They can initiate new theory, or reformulate, refocus, and clarify existing theory.