Designing sound testing activities is a challenge. Some would even argue that is more difficult to test something than it is to teach it. If done right, testing activities will not only measure learner progress, but also reinforce key knowledge, correct common misconceptions, guide learners in the learning process, build confidence in own knowledge, motivate to perform better, reduce fear of formal exams and provide trainers with actionable data on performance. In his book E-Learning by Design, William Horton defines 8 components for testing items. While these are not mandatory for each testing activity, they should be considered when designing for testing.