In view of its acceptability by the students and the faculty, it was felt necessary to strengthen some of the initial chapters of both "Heat Transfer'' and "Mass Transfer" relating to the fundamentals. Thus, the first chapter of "Heat Transfer" section and the first two chapters of ''Mass Transfer'' section have been revised. In addition, a few more typical numerical examples along with solutions have also been added. This textbook efforts have been made to cover the entire syllabi of students of engineering colleges and institutions. This book is therefore suitable for students appearing in GATE, IGNOU and other competitive examinations. I hope this book will meet the long felt need of the students and professionals. I, hope, these additions will add to the value of the textbook. However, comments and suggestions by the users are always welcome. Prof. (Dr.) G.K.Roy