The symposium on which this book is based originated after Tom Strom organized a successful American Chemical Society (ACS) symposium in March 2016, on the Posthumous Nobel Prize in Chemistry. Afterward, Vera Mainz pointed out that the chemists represented in that symposium and its subsequent symposium volume were "all dead white guys." The fact that only white men were included in the first symposium partly reflects the prevailing past (and continuing) gender imbalance in chemistry, but it also shows the power of the Matilda effect, first articulated by Matilda Joslyn Gage (1826-1898). The Matilda effect is an implicit bias against acknowledging the achievements of women scientists, whose work is often attributed to their male colleagues. An implicit bias is one which is not conscious or deliberate, but nevertheless real. The gender imbalance in the previous symposium was also noted in the on-line comments for the Chemical and Engineering News article that reported on it. Redressing that imbalance was the purpose of the current symposium entitled "Ladies in Waiting for the Nobel Prize in Chemistry. Overlooked Accomplishments of Women Chemists." This symposium, which took place in August 2017, was sponsored by the ACS History of Chemistry Division (HIST), the Women Chemists Committee (WCC), and ACS President Allison Campbell. In the Preface to The Posthumous Nobel Prize in Chemistry, Volume 1: Correcting the Errors and Oversights of the Nobel Prize, Mainz and Strom noted that "any chemist with a decent background in chemical history could readily add other deserving chemists to our list." Undoubtedly, this is also the case for the current symposium: There are other women as well as noteworthy scientists of color who could have been included. These men and women should be the topic of a future symposium. By highlighting this group of extraordinary women scientists, this book raises awareness of the Matilda effect, but more importantly, it honors them and their accomplishments.