This book, consisting of four chapters, contains 138 problems in differential equations. The topics covered are: first order differential equations, Cauchy problems, uniqueness and existence theorems, higher-order differential equations and systems of differential equations. Each chapter is divided into four parts: definitions and basic results (I), solved problems (II), additional problems (III), hints and answers for additional problems (IV). There is a table of contents, bibliography and an index, which permit easy location of a special topic and also a quick access to the hints and solutions. The book is mainly addressed to undergraduate students in mathematics as a companion and complement to the basic course in Ordinary Differential Equations, but may also be a valuable tool for the undergraduate and graduate students in engineering, computer science, economics and the natural sciences.