This User's Manual describes how the Early Childhood Longitudinal Study, Kindergarten Class of 2010-11 (ECLS-K:2011) was designed and conducted, as well as the contents of the restricted-use data file and how to use the Electronic Codebook (ECB) software. The ECB helps users to create customized data files with only the variables needed for analysis. This manual is only available on the ECLS-K:2011 Restricted-Use Kindergarten Data File and Electronic Codebook CD (NCES 2013-060).