Instructional packages (PAKs) are effective in promoting vocational learning as they provide an organized procedure for delivering self-paced instruction to individual trainees on a personalized basis. Some of the advantages of PAKs are that they free an instructor from the role of full-time transmitter of skills and knowledge, reduce equipment needs, and assure that each trainee is exposed to a uniform training program. Based on pre-determined job tasks and performance requirements, each PAK is made up of four fundamental components: (1) the introduction, which gives an overview of the PAK, the terminal performance objectives, and the procedure for using the PAK; (2) a pre-check which is designed to determine the extent of trainee competency prior to PAK exposure (the results can be used to diagnose and prescribe which instructional modules a trainee needs); (3) printed modules of instruction (the bulk of the package) which contain an enabling objective, a training activity, resource, and feedback; and (4) the criterion referenced measure or posttest, which assesses the trainee's achievement of the terminal objective. While some trainees are proficient with printed materials, others require different types of media, such as audio and video cassette tapes, sound filmstrip, and sound slide programs. Emphases should be placed on those forms of media which are accepted by trainees and can be produced within a reasonable amount of time with available equipment. PAKs and media should be developmentally tested (individual product tryouts, small group tryouts, and field tested) against criterion referenced measures before being implemented. Observations of the products in use and data collected during each program offering should be utilized to continually improve the reliability of PAKs and media. (JH)