The Singapore Longitudinal Early Development Study (SG-LEADS) seeks to understand factors that can enhance or hinder Singaporean children's early childhood development with an aim to inform public policies that can help each child reach his or her potential. SG-LEADS is a nationally representative household survey that focuses on Singaporean households with children aged 0-6 at the baseline. It adopts a multi-stage probability sampling - clustered and stratified sampling strategy - with an oversample of the low-income households residing in 1-3-room HDB (Housing Development Board) public housing units. In-home face-to-face interviews were conducted on the computer-assisted personal interviewing (CAPI) systems. The baseline survey was conducted between 2018 and 2019. Up to two eligible children and their primary caregivers were interviewed in each household. In total, 5,005 Singaporean children aged 0-6 in 3,476 households and their primary caregivers were successfully interviewed. In 2021, 4,351 children in 3,017 households were successfully re-interviewed. The contents of SG-LEADS are designed based on theories in multiple disciplines including sociology, psychology and economics about how multiple contexts (home, out-of-home care institution, community and state) interact to shape the multiple domains of child development. The survey includes assessments of children's motor, social-emotional well-being, language and cognitive skills, and biometric measures. Rich data about the family's socioeconomic, demographic and cultural backgrounds, family structure, family relations, home environment, social support, food security, financial distress, public program participation, and neighborhood characteristics and cohesion were collected. Comprehensive information was obtained about the target child's early childcare and preschool arrangements, children's time use (through time diaries), technology use, enhancement activities, nutrition intake and more. Primary caregivers' social-emotional well-being, cognitive skills, and parenting behavior were also assessed. In Wave 2, a special module about the family's COVID-19 experiences and responses was added. Descriptive statistics were presented on the study website. Multivariate analyses were conducted based on the SG-LEADS dataset with a variety of robust methodologies such as structural equation modeling, fixed effect analysis, lagged dependent variable model, hierarchical regression analyses, mediation analysis, propensity score matching, and so forth. Thus far, 14 journal articles have been published with a dozen or so papers under review. These analyses cover a wide range of topics, including but not limited to, 1) the impact of socioeconomic status on children's development such as infants' vocabulary, children's academic achievement and socio-emotional development, 2) the impact of paternity leave-taking on child outcome (3) how food insecurity affects children's behavior, (4) family experiences and resilience during COVID-19, (6) childcare arrangements and children's behavior and cognitive development, (6) children's ability to delay gratification in early childhood, (7) children in cross-national families, 8) children's time use, (9) family and community social capital and child development. The rich data in this longitudinal study provide many opportunities to research a wide range of topics related to early child development in an Asian context. This dataset holds tremendous potential to uncover valuable insights and inform evidence-based policy interventions to support optimal early childhood development. International comparative studies can also be conducted with similar surveys conducted in other countries.