Understanding the bacterial cell envelope provides valuable insights for two crucial areas: the discovery of new antibiotics and the understanding of microbe-host interactions. The cell envelope serves as a prime target for antibiotic development, as its unique components and processes can be exploited to disrupt bacterial growth and survival. By studying the cell envelope’s structure, biosynthesis, and transport mechanisms in diverse organisms, we have been able to identify novel targets for antimicrobial intervention. Additionally, the cell envelope’s role in microbe-host interactions aids in developing strategies to manipulate or modulate these interactions. This knowledge can lead to the development of therapies that promote beneficial host-microbe relationships while mitigating pathogenicity, opening new avenues for combating infectious diseases.