This study investigated inservice teachers' assessment competency as a function of measurement training and years of teaching. Data were collected from 311 teachers on a 67-item Assessment Practices Inventory (API). Seven composite scores were formed based on the underlying dimensions from a principal factor analysis. A 2x3 MANOVA was conducted to examine the effects of measurement training and years of teaching on teachers' perceived competency in the seven assessment categories as reflected in the composite scores. Multivariate interaction effects between measurement training and years of teaching were significant. Subsequent examination revealed significant multivariate simple effects of measurement training at four or more years of teaching in two factor analyzed assessment categories. Follow up comparisons between means indicated that among teachers who had taught four or more years, those with measurement training scored significantly higher than those without measurement training on standardized test results interpretation, classroom statistics, and using assessment results in decision making. This group also scored significantly higher on performance assessment and information observation. Appendixes contain tables of data and description of seven standards for teacher competence of educational assessment of students. (Contains 3 tables and 40 references.) (Author/JB)