Charter school authorizing is a powerful strategy for making excellent public schools and educational opportunities available to all students and communities, especially those who are historically under-resourced. Done well, authorizing increases student achievement by expanding the supply of quality public schools. Because authorizing is a continually developing profession, these professional standards must likewise evolve in response to the growth and complexity of the ever-growing charter school sector. "Principles & Standards for Quality Charter School Authorizing" derives from the National Association of Charter School Authorizers' (NACSA's) vast experience, research, and work with authorizers across the nation. Accordingly, NACSA revisits and updates them regularly to address current challenges and reflect the latest lessons drawn from practice, research, and analysis. These "Principles & Standards" begin with three clearly stated Core Principles, followed by more detailed Standards and accompanying practical guidance that authorizers often seek. The Core Principles are broad, bedrock values that authorizers should uphold consistently throughout their pursuit and implementation of the Standards. The Standards are presented in five sections, each of which is introduced by a brief statement that summarizes the scope of the Standards that follow. Most of the Standards are "essential standards," meaning that authorizers at every stage of development should place priority on following them. [For the previous edition (2018), see ED595188.]