The substance and dynamics of secrets were elicited and analyzed for 180 children at three grade levels, to examine developmental trends and gender differences. The recorded frequencies were subjected to loglinear analyses. The results, which revealed a grade effect regarding topics of secrets, indicated a developmental shift in topics with age from secrets pertaining to possessions to secrets pertaining to interpersonal relations, heterosexual involvement, and moral transgressions. A grade effect also emerged regarding reasons for secrecy; a shift was indicated from need for exclusiveness typical of younger children to socially embedded reasons for secrecy characteristic of older children. A gender main effect regarding topics of secrets indicated that boys more often than girls bear secrets pertaining to possessions and moral transgressions, whereas girls tend more often than boys to bear secrets pertaining to family issues. No gender effect was evident, however, in regard to reasons for secrecy. The developmental trends in both aspects of secrecy investigated may be conceived in the framework of a dual shift from separateness to relatedness and from true latency to late latency.