Although a prolific composer, Reicha made his greatest contributions as a theorist and teacher. He wrote this harmony method in 1818, shortly after being appointed professor of counterpoint and fugue at the Paris Conservatoire. It is among the first textbooks to use examples written expressly for the text (rather than preexisting music) and became a fixture in the school's curriculum.

As per Grove's Dictionary, the treatise stresses the point that theory must be justified by practice and that the pupil must learn about contemporary usage, not solely about ancient principles.

Reicha was a lifelong friend of Beethoven and his pupils included Liszt, Berlioz, and Ceasar Frank.