This book is directed to Lectures and students, and researchers in Civil Engineering field and interested to study; and also to investigate clayshale in Indonesia. There are many infrastructures built on these layers, however, after a few years all clayshale layers become to slide and to collapse the soil foundation, and to affect all infrastructures above. We hope this book could be a valuable information and help to develop the similar research for all countries in the world which have clayshale layers, thus in the next time, we could extend the research to create instruments and methods to clarify the important parameter of clayshale used in the infrastructure detail engineering design. This book is a partial achievement of research and is far from perfect, as the author will continue to make improvements in the future.