Spitz approaches the problem of treating infants psychiatrically by making a survey of common disturbances in their psychic development, reviewing the known etiological factors and then suggesting appropriate remedial measures. He differentiates four methods of approach to treatment: prophylactic, restitutive, substitutive, and modifying. 'The sum total of our findings on psychotherapy in the preverbal stage is that this has to consist of an environmental manipulation, both in regard to love objects and inanimate objects. The needs of the child are simple and an intelligent observation of the child's environment will readily disclose which of these needs is unsatisfied.'