The development of modern pulsed lasers with power densities larger than 16 ?2 10 Wcm and with very short pulse duration in the femtosecond regime enables experimentalists to study elementary processes such as chemical - actions and excitation mechanisms in di?erent areas in physics in the time domain. In parallel to the experimental investigations, analytical and num- ical studies of laser-driven atoms and molecules with a limited number of degrees of freedom are performed. These theoretical investigations have led to the prediction and/or the explanation of a large variety of partly count- intuitivephenomena. Amongthosearethegenerationofhighharmonicsusing laser-excitedatomsormolecules,theionizationofatomsabovethecontinuum threshold, the stabilization of atoms against ionization in very strong ?elds, counter-intuitive pulse sequences to selectively populate vibrational states in moleculesand,lastbutnotleast,thecontrolofchemicalreactionsbyspecially tailored laser pulses. This book originated from a course, that I have been giving on a regular basis since 2000 for advanced undergraduate and graduate students at Te- nische Universit. at Dresden. It o?ers a theoretically oriented approach to the ? eld of laser-driven atomic and molecular systems and requires some kno- edge of basic classical and quantum mechanics courses as well as of classical electrodynamics. The book has two introductory chapters in Part I that pave the way for the applications in Part II. Part I and also Chap. 3 of Part II contain of textbook knowledge that is needed to understand the rest of the book. The material presented in the last two chapters is close to the recent l- erature.