NGSS Early Implementers is a six-year initiative created to help eight California school districts and two charter management organizations, supported by WestEd's K-12 Alliance, implement the Next Generation Science Standards (NGSS). Administrators need learning opportunities if they are to adequately understand the substantial shifts of the Next Generation Science Standards and support teachers in implementing them. Accordingly, the K-8 NGSS Early Implementers Initiative has consistently expanded the professional learning it provides for administrators, particularly for site administrators, who generally have the most contact with teachers. This tenth evaluation report in the series, intended for site and district administrators and state leaders, highlights: (1) the professional learning strategies used by the Initiative to engage and empower administrators to support NGSS implementation (includes two district vignettes); (2) the impact of the professional learning on administrator understanding and actions; (3) the challenges experienced by the Initiative in trying to involve administrators; and (4) recommendations for increasing administrator help with science implementation.