What is the relationship among Kirkpatrick’s four levels of evaluation?

Kirkpatrick’s four levels of evaluation are a tool used to measure the effectiveness of training programs. The four levels include reaction, learning, behavior, and results. The relationship between them is hierarchical; each level builds on the one before it. Reaction is focused on participants’ immediate reactions to the training program and gauging whether or not they enjoyed it. Learning assesses how much knowledge or skills have been acquired as a result of the training program. Behavior looks at whether or not changes in behavior have occurred due to participation in the program. Finally, Results evaluates what long-term effects have been achieved from participating in the program and if any organizational objectives have been met as a result of it.