Book excerpt: Mathematical control theory has evolved from the study of practical problems in engineering and sciences to the elaboration of deep, important concepts in mathematics and applied sciences. This volume concerns contemporary trends in nonlinear geometric control theory and its applications. It is a fine collection of papers presenting new results, relevant open problems, and important applications regarding academic and real-world problems.The book is dedicated to Velimir Jurdjevic whose scientific activity has been influential in the research of many of the authors. It contains a number of articles specially written by colleagues and friends of Vel Jurdjevic, all of them leading applied mathematicians and control theorists. There is also place for surveys on topics of current research which present the state of the art of modern geometric control theory. Finally, the volume contains several new mathematical ideas generated by geometric control theory techniques, which may initiate new directions of research beyond control theory.