This is a book about worked exercises in Theoretical Mechanics, designed to accompany a one-semester course. It was born from the Italian university tradition of splitting basic courses into a purely theoretical part, called Lezioni, and a practical part, called Esercizi e Complementi. In fact, this book is based on experience gained by the authors in teaching Esercizi e Complementi at the Universities of Firenze, Milano, Pavia, Pisa and Napoli and at the Italian Naval Academy in Livorno. The book is more then a mere collection of exercises. Each chapter contains an introductory part presenting some relevant topics of the theory, which is then applied to selected problems which are completely worked out. In this way, the student learns what is necessary and may test his understanding directly from the exercises. The authors use the language and methods of today's Mathematics, so providing a modern and concise treatment of the subject. This enables students to acquire a useful methodology, preparing them also for subsequent Physics courses. The choice of the contents has been carefully selective in order to have a balance between theory and applications. Special emphasis has been paid to "model exercises" related to topics that the student will encounter in other branches of Physics. The result is an elegant treatment with only basic, essential material. The book can be useful equally to students in Engineering, Physics and Mathematics. It is ideal for students studying by themselves.