Since the Kirkpatrick four levels were first published in November 1959, they have become the industry standard for training evaluation. They have also been widely misunderstood. On the 50th anniversary, this book provides an accurate account of the development of the four levels and the complete, modern application of the model's principles. The unedited text of the original four articles is included in this book. Don Kirkpatrick himself tells the story of where the four levels came from, assisted by others like Jack Phillips who were key in the growth of the model. The most detailed explanation available of the Kirkpatrick Foundational Principles is provided. The new Kirkpatrick Business Partnership Model is shared in a step-by-step format that guides you through all stages of training and development. This book is a must-have for all training professionals who want to provide and demonstrate true value to their business partners using the latest Kirkpatrick methodology.