Barring a finding that people were coerced in voting, the Community School of Excellence announced it would abide by what it described as a "historic unionization vote" by employees Wednesday.
"The union campaigned on the theme, 'Say Yes to CSE Success!' and we trust that the union and all our employees will go forward together with commitment and dedication to our mission," Superintendent Mo Chang said in a statement released late Wednesday night.
The St. Paul school becomes the second unionized charter school in the state.
The vote to form a union affects all of the school's approximately 120 employees, and comes nearly a year after the state Department of Education shed light on management issues at the North End area school by calling for an investigation into the alleged misuse of funds as well as allegations that it engaged in retaliatory employment practices.
An independent investigation depicted a tense working environment in which employees were fearful of disagreeing with Chang. She survived a call for her dismissal.
The K-8 school, which teaches Hmong culture and language, has seen remarkable growth. This spring, it had 958 students -- more than five times the number when it opened in 2007.
The run-up to Wednesday's vote had been contentious, with Education Minnesota filing six charges of unfair labor practices against the school.
Board Chairwoman Patti Hessling said in Wednesday's statement: "We believe the charges are without merit and will defend them if they are not withdrawn."
Wednesday's vote now awaits certification by the National Labor Relations Board. The next step, then, would be contract bargaining.
"I've often said a union contract is like the First Amendment for educators," Education Minnesota President Denise Specht said Wednesday. "It permits them to speak out without fear about what's happening in their schools. Those conversations are vital for keeping families engaged and schools focused on preparing students for successful lives."