Median sternotomy remains the most common surgical incision used by cardiothoracic surgeons. The purpose of this paper is to summarize the pros and cons of the different sternal closure techniques and their principles by concentrating on their clinical and biomechanical aspects. Unfortunately, there are no adequately powered, prospective randomized controlled clinical trials comparing different osteosynthetic techniques with regard to sternal instability. Therefore, the level of evidence is rather weak. Furthermore, there is no consensus among biomechanical studies on the optimal sternal model and the effectiveness of different methods for sternal closure. Key factors in preventing sternal dehiscence are compliance with rules of aseptic surgery and osteosynthesis, suture of rectus fascia respecting anatomic compartments, additional reinforcement of the lower third of the sternum and careful attention to hemostasis.