This book is intended primarily for students taking general coursesin atomic and nuclear physics. It contains, however, a sufficientlylarge number of problems lying beyond the general course to makeit also useful in the study of some special courses.The volume contains over 1000 problems. The solutions of themost complicated of them are provided with detailed explanation.A brief summary of the basic terms and definitions at the beginningof each chapter also makes the solving easier. The fundamentalphysical constants and reference tables and graphs are given in theAppendix. Both the Periodic Table of the elements and the table ofelementary particles are also provided.The Gaussian system of units is employed throughout the book.All initial data and numerical answers are given with due regardfor the accuracy of appropriarte values and the rules of operationwith approximate numbers.In conclusion, the author takes pleasure in expressing his deepappreciation to his colleagues from the Moscow Engineering PhysicsInstitute and all those who submitted their comments on certainproblems and thereby contributed to the improvement of the book.