From 2010 to 2014, Scaling What Works was a multi-year learning initiative of Grantmakers for Effective Organizations (GEO) to expand the number of grantmakers and public sector funders who are working together to grow the impact of high-performing nonprofit organizations. Through the Initiative, GEO offered training, networking opportunities, and a host of tools and resources to better equip grantmakers to help nonprofit organizations to plan, adapt and grow their impact. From 2011 to 2014, GEO engaged Informing Change to evaluate the progress, accomplishments and challenges of the Scaling What Works initiative. As part of this evaluation, Informing Change spoke with over 75 representatives of philanthropic organizations and more than 20 representatives of nonprofit organizations to better understand their experiences and strategies related to growing impact. This brief provides key evaluation highlights and takeaways that are most relevant to grantmakers, both those who are new to the concept of growing impact and those who are already immersed in the work.