Recommended practices for defining competencies are provided. IEEE P1484.20.3/D1 (February 2022), a technical standard for competency definitions data, is supported. Recommended practices are given for defining the kinds of information that IEEE P1484.20.3/D1 (February 2022) encodes as interoperable data, i.e., data that defines a skill, knowledge, ability, attitude, habit of practice, behavior, or learning outcome.