This book provides an introduction to q-series that would be accessible to calculus students, its main purpose is to offer beautiful theorems to the reader along with, in many instances, equally beautiful proofs that cannot be found elsewhere, except possibly in the authors own papers. those who already love q-series will find much to admire and enjoy in Hirschhorns book The Power of q. Those desiring an introduction to the subject can also enjoy it. (Bruce Berndt, The American Mathematical Monthly, Vol. 126 (2), April, 2019)