This Race to the Top - Early Learning Challenge (RTT-ELC) annual performance report for the year 2015 describes Delaware's accomplishments, lessons learned, challenges, and strategies Delaware will implement to address those challenges. Delaware made significant progress in four primary areas in Year Four: (1) continued success in implementing Early Learning Challenge activities and exceeding outcome targets; (2) building state and community awareness and support of a high-quality early learning system; (3) establishing a permanent governance structure for the state's early learning system and ongoing leadership; and (4) building a plan for sustaining key Early Learning Challenge initiatives and progress after the Early Learning Challenge funding expires. Key performance targets met or exceeded in Year Four include: (1) The number of early learning programs participating in the state's quality rating and improvement system has grown from 134 to 565, with 66% of participating programs rated in the top quality tiers, exceeding the target for performance; (2) More than 79% of children with high needs (16,974) were served in programs participating in Delaware Stars in 2015; (3) Delaware exceeded its performance measure for serving children with high needs in DE Stars top tier programs, with 63% of children with high needs (10,193) served by Star 3, 4, and 5 programs; and (4) The number of early learning professionals receiving T.E.A.C.H.® Early Childhood scholarships for working toward early childhood degrees or credentials has doubled since 2011; up to 209 scholars in 2015. Success in these and other key grant performance measures clearly indicate that the grant has influenced positive system change--directly benefiting Delaware's earliest learners and their families. The Office of Early Learning (OEL) also learned some valuable lessons on how best to educate and engage new stakeholders in the state's early learning work. Outreach efforts were intensified, and all presentations started with brain research and early learning's connection to not only school success, but economic development, crime reduction, and thriving communities. [For "Race to the Top - Early Learning Challenge Year 2015 Progress Update," see ED583454.]