'As psychologists and educators adopt a broader approach that considers the child as a whole, living, feeling person, they will find Heinz Werner's classic work to be of great value.' (William Crain, City College of New York) 'Heinz Werner's seminal work on mental development has provides the kind of generative and rich theoretical framewoerk that contemporary scholars need so much. Vital to anyone who wants to think deeply about developmental psychology.' (Susan L. Engel, Williams College) 'The republication of Comparative Psychology of Mental Development makes available to new generations of developmental scientists and students the creativity, scope, and integrative vision of this master scholar.' (Richard M. Lerner, Tufts University)