 Baldwin's writing career began in earnest when her first novel, "Mavis of Green Hill", was published in 1921 by Boston publisher Small, Maynard & Company.Six years later, in 1927, she sold her first serial to a magazine, Good Housekeeping.This led to more serials for "women's magazines" that published romance novels as six-part serials, and her popularity with the middle-class and working women audience quickly grew.