Although becoming a grandmother represents an important transition in a woman's life, it has received scant research attention. This study used the model of growth developed by Schaefer and Moos in an attempt to identify personal and environmental resources that may contribute to a first-time maternal grandmother's mental health and her perceptions of costs and sense of personal growth. One hundred and two Israeli women completed a series of questionnaires twice: (1) during their daughter's first pregnancy and (2) following the birth of their first grandchild. The independent variables included the personal resources of education, physical health, self-esteem, attachment style, and self-mastery and the environmental resources of grandmother's perception of level of intimacy with her daughter and active involvement with the grandchild. Findings reveal that education, attachment style, self-esteem, and self-mastery are associated with mental health, perception of costs, and experience of personal growth. The pattern of the correlations that emerged indicates that the transition to maternal grandmotherhood, a normative life event, may evoke both positive and negative cognitions and emotions.