Evaluating Training Programs: the Four Levels of Learning Evaluation (Kirkpatrick Model)
Donald Kirkpatrick's and Jack Phillips' 4 Levels of Learning Evaluation model helps to evaluate training programs. As you proceed through each of the levels, the training evaluation becomes more difficult, requires more time, but provides more valuable information. The 4 levels of Kirkpatrick's Evaluation Model are:

Level 1.
Reaction: what participants thought and felt about the training (satisfaction; "smile sheets")
Level 2.
Learning: the resulting increase in knowledge and/or skills, and change in attitudes. This evaluation occurs during the training in the form of either a knowledge demonstration or test.
Level 3.
Behavior: the transfer of knowledge, skills, and/or attitudes from classroom to the job (change in job behavior due to training program). This evaluation occurs 3-6 months post training while the trainee is performing the job. Evaluation usually occurs through observation.
Level 4.
Results: the final results that occurred because of attendance and participation in a training program (can be monetary, performance-based, etc.)
According to Kirkpatrick (Evaluating Training Programs (3rd edition)), it's important that "none of the levels should be bypassed simply to get to level that the trainer considers the most important."
Certain authors have suggested an additional 5th level of evaluation to Kirkpatrick's model:
- JJ Phillips has argued for a Level 5.
Return On Investment (ROI), which is essentially about comparing the fourth level of the standard model to the overall costs of training.
- Roger Kaufman has argued for a Level 5.
Impact of the organization on external clients and society.