This book presents a range of observations about impact-oriented accelerators and the entrepreneurs and ventures that they attract and sometimes work with. Relying on data collected through the many programs that partnered with the EDP from 2013 to 2017, these observations provide consistent evidence that accelerators are influencing short-term commercial performance. It should be heartening for supporters of these programs to see that, on average, one dollar spent on acceleration leads to more than one dollar of incremental funding for participating ventures. The average effects are even more impressive when we consider that accelerators are implicated in positive growth outcomes for the most promising entrepreneurs, and in the negative growth outcomes experienced by participants that are (arguably) less promising. However, these accelerator effects are not equal across the board. When we zoom in to provide specific insights on these program-to-program differences, the EDP data become more equivocal. With a few exceptions, it is difficult to identify specific program choices that correspond systematically with better accelerator outcomes. The one thing that we can say with some degree of certainty is that accelerators do not currently work as well for certain emerging-market ventures, or for ventures launched by all-women founding teams. Thus, while accelerators appear to be a promising intervention for stimulating ‘entrepreneurial dead spaces,’ more work must be done to ensure they maximize their potential. Much of this work will be done by future program managers—innovating with donors, mentors, and investors—as they continue to adapt their offerings to bolster the quality of support offered to still-neglected entrepreneurs. However, we close the book by calling for additional heavy lifting by researchers, who must bolster collective learning efforts so that we lose less of the potential inherent in the world’s impact-oriented entrepreneurs.