Two approaches to the measurement of teacher efficacy were investigated to determine whether teachers' sense of self-efficacy is a self-referenced or norm-referenced construct. Two forms of an instrument consisting of 25 teaching problem situations were developed: one required self-referenced responses, while the other required norm-referenced responses. The two forms were randomly distributed to 65 classroom teachers enrolled in graduate classes at the University of Florida (Gainesville). In addition, two items measuring teacher efficacy from a Rand Corporation study and the Marlowe-Crowne Scale of Social Desirability were administered. Efficacy appears to be a norm-referenced, rather than a self-referenced, construct. Teachers appear to evaluate their effectiveness in terms of their performance in comparison to the performance of other teachers. Social desirability bias was a significant factor in the use of self-referenced vignettes. Three tables and one figure illustrate the study. (Author/SLD)