The aim of this literature review is to examine inclusive education in the mainstream secondary education classroom, namely how participation in training, support, and attitudes and perceptions influence the success of inclusive education. Several articles were reviewed that researched inclusive education to determine the opinions of teachers who have implemented inclusive education into the mainstream secondary classroom and whether or not support and training influenced the success of inclusion. Teachers’ perceptions on inclusive education are important to investigate. This will determine where teachers’ perceptions and attitudes towards and knowledge of inclusive education as well as principals’ support and expectations of teachers in implementing inclusion were predictors of effective teaching practices in the mainstream classroom. Literary researched showed that attitudes towards inclusion and knowledge of inclusion predicted the effectiveness of teaching practices and the principals’ expectations and how they correlated with its success.