This module, the third of four units about vocational competency measurement, is module 19 in the Vocational Education Curriculum Specialist series. The purpose stated for the document is to help in the development of both written and performance competency tests based on the needs identified for testing a particular program and the standards and priorities established for job-related tasks. Content is organized into four sections, each of which focuses on one goal and two or more objectives. Section 1 summarizes important considerations in vocational competency-test development, including test validity, reliability, practicality, and testing individuals with special needs. In section 2, important considerations in designing initial test specifications are overviewed. Sections 3 and 4 discuss the critical tasks in developing paper-and-pencil and performance tests. Each section concludes with individual study activities, discussion questions, and group activities. Self-check items and possible responses to them are appended for use as a pretest and review of the module content. (YLB)