This book is the result of a research financed by the National Research Council (CNPq), through which the issue of child aggressiveness was investigated. The theme has generated concern worldwide, which mobilized the researchers to understand the phenomenon and seek ways to help children in a public school in São Paulo. The general objective of the research was to investigate the possible causes of aggressive manifestations in a child of a public school of early childhood education and to carry through intervention in the sense of contributing to the quality of its interpersonal relations. To do so, it had as specific objectives: 1 - to identify the relationship difficulties presented by the child; 2 - to reconstruct her life history; and 3 - to provide the child with moments of shelter, expression and possible conflict elaboration through playful activity.