Rakúsky narodená britská psychoanalytička, ktorá vyvinula nové terapeutické techniky pre deti, čo malo významný vplyv na detskú psychológiu a súčasnú psychoanalýzu. Bola poprednou inovátorkou v teoretizácii teórie objektových vzťahov.
Melanie Klein's writings, particularly on infant development and psychosis, have been crucial both to theoretical work and to clinical practice. 'Envy and Gratitude' her last major work, introduces her theory of primary envy.
She made possible the extension of psycho-analysis to the field of early childhood, and in this way not only made the treatment of young children possible but also threw new light on psychological development in childhood and on the roots of adult neuroses and psychoses.