The title question is discussed in six sections. Structural variables and issues are discussed in subsections concerning: the sex of child, the kindergarten program's day length, type, entrance age, group size, classroom aides and arrangements, and policies on promotion, failure, and retention. Interpersonal variables are explored in terms of whole language, the process of learning to read through experience, early writing, metacognitive skills, and theories of child development. Ideal kindergarten teachers' characteristics are considered in subsections on: identifying students' abilities, respecting personhood, modeling calmness and coping, providing developmentally appropriate learning experiences, becoming skilled at science and mathematics, enriching language, using fair rules, cultivating flexibility and attunement, providing psychological safety, providing many books, engaging in turntaking conversations, self-esteem, teaching children to identify consequences of behaviors, developing a repertoire of disciplinary techniques, boosting nutrition, and relieving stress on students. Decisions about assessment are discussed with regard to kindergarten screening, assessment of developmental appropriateness, and monitoring of children's progress. Changes in teacher education and school practices are described in discussions of outreach to parents and the community. Discussion of kinds of learning needed in kindergarten centers on motivation, reasoning, thinking skills, and teacher beliefs and the implementation of changes. A total of 167 references are cited. (RH)