There is ample evidence as to how the modern masters, in their shared pursuit of formal and constructional inventions, variously referred to past examples they had freely chosen as guides to inspire and support them in their strenuous pursuit of new things. However, buildings shaped like soft clouds and gelatinous bowels; or the spiked, bravura pieces designed by today's fashionable architects, for example; have no relation with either construction or its history.Louis Kahn kept form, structure and history paradigmatically together. This book systematically reviews the intense structural experimentation that marked Kahn's work since the beginning and would eventually lead him to an almost constant adoption of 'hollow' structural forms. By reviewing his long and intense journey, this book underlines how Louis Kahn, in each of his works, succeeded in awakening our interest in a new, 'fascinating' structure and at the same time fed our emotions with his deeply meaningful, universal and timeless forms.