BACKGROUND: Sub-muscular positioning of breast implants requires interrupting as well as disinserting both the abdominal and sterno-chondral fibers of the pectoral muscle; this can produce a muscular strength reduction which reveal bothering and is often detected in some daily motions, such as cutting bread into slices. MATERIAL AND METHODS: The revision of anatomy and literature induced the authors to search for a conservative approach for breast augmentation. They describe a new technique defined “Tri-plane” where the muscular fibers are not cut but simply split to create the pocket for breast implants. RESULTS: Our experience evidenced that this technique gave good aesthetic results together with a more significant projection of the NAC without any strength diminution either in adduction or abduction of the arms. CONCLUSIONS: This technique is a valid alternative to other techniques of breast augmentation as it conjugates the advantages of sub-glandular and sub-muscular implants without muscular deficit.