The panel study on Korean children, undertaken by the Korea Institute of Child Care and Education (KICCE) aims to collect and provide nationwide longitudinal data on the effects of childcare policies and local communities, the effectiveness and functions of childcare institutions, childcare issues and needs, and the development characteristics of children at each development stage via investigation into the developmental trends of Korean children starting from birth. In the pursuit of these longitudinal goals, a panel study model was first developed in 2006. In the following year, 2007, based on the model, a pilot study was implemented in preparation for the up-coming first year investigation undertaken in 2008. In 2008, the first year study started according to the sample design and research methods planned over the past two years. The panel study adopted a multistage stratified sampling method. The first sampling stage involved selecting medical institutions with the record of 500 or more parturition cases annually and these institutions were allocated proportionally among six major districts (Seoul, Seoul-Incheon, Chungcheong/Kangwon, Gyeongbuk, Gyeongnam, Jeolla) in Korea. From the thirty institutions sampled in the first stage, households with the newborn babies born between April and July, 2008 were sampled in the second stage, totaling 2,078 final subjects in the first year panel study. The study consists of a two-fold investigation, one of which is general in nature, and the other more in-depth. The general study is carried out annually from the time of birth of newborns in 2008 to the year 2015 of their elementary school admission and is planned to be followed up with two studies in 2017 and 2020. The contents of the research were systematically categorized, involving the traits and environments surrounding the children: these included comprehensive data on the characteristics of the children, parents, families, childcare support services, local communities, and childcare aid policies. The study consists of a two-fold investigation, one of which is general in nature, and the other more in-depth. The general study is carried out annually from the time of birth of newborns in 2008 to the year 2015 of their elementary school admission and is planned to be followed up with two studies in 2017 and 2020. The contents of the research were systematically categorized, involving the traits and environments surrounding the children: these included comprehensive data on the characteristics of the children, parents, families, childcare support services, local communities, and childcare aid policies. In 2011, the fourth year panel study was carried out with 1,754 households, in which parents completed questionnaires, Computer-Assisted Personal Interviews (CAPI), Receptive and Expressive Vocabulary Tests (REVT) for the assessment of the child's language development, and a home environment scale. As the newborns in 2008 became three-years-old this year, the panel study strived to build comprehensive data on child development and the effects of their environments by expanding the research range to include the childcare institution, a key microsystem that impacts upon child development. By utilizing a web-questionnaire method to full-time or part-time teachers of preschools, kindergartens, and half-day private tutoring institutions, data on children and their institutions were collected. In addition to the general research, the in-depth study is planned to be conducted on approximately 10% of the total number of subjects in the general study at three critical periods, using a variety of methods such as observations, interviews, individual performance task tests, amongst other methods. The first year in-depth study in 2009 also assessed the overall development of the young children, the children's secure attachment with their mothers, their temperament, and the personalities of their mothers utilizing the Korean Bayley scales of infant development, the Korean Attachment Q-set, the ECBQ of 18 subscales, and the Personality Assessment Inventory, respectively. In the current year, taking advantage of the data accumulated over the last three years, a booklet of the panel study (tentatively named "A Series of Data from the Panel Study on Korean Children") was published and, hence, permitted non-professionals to readily approach the research results. In addition, KICCE held a number of policy forums and seminars using the panel data to explore policy measures aimed at dealing with the national agenda of low fertility. The International Seminar and The Second Annual Conference of the Panel Study on Korean Children was held and, in so doing, raised the international profile of KICCE. Moreover, by visiting Battelle Research Center which is presently proceeding with the National Children's Study (the largest panel study on children in the world), KICCE was able give due consideration to the promotion of future cooperation in connection between the two panel studies. In addition, two post-board reports were presented to the Society for Research in Child Development. The preliminary analysis was based on the data of the third-year general research and some of the more distinctive results can be summarized as follows: The results of the Denver II screen test revealed that 89.8% of the total children fall into the normal range and 10.2% were found to be suspected of developmental delay. The follow-up planned parenthood was found to be mostly effected by the mother herself (70.6%) and the husband (22.3%). Fathers spent on average 6.69 hours during week days and 8.18 hours during weekends engaged in childcare, whereas mothers spent 29.90 hours and 15.34 hours, respectively. Primary childcare services utilized were classified to be individual surrogate caregivers (18.6%) and childcare centers (79.4%). In regard to the financial support policy for fully funding childcare institutions, 75.8% of parents responded thus; "I will plan an additional childbirth" and 17.2% responded "I don't know."