Attorney-client privilege is a fundamental principle in the legal profession. It ensures confidential communication between clients and their attorneys. In criminal defense cases, this privilege enables clients to discuss their case openly with their lawyer. They do not have to fear that their communications will be disclosed to others, including the prosecution. This confidentiality allows the attorney to understand the case and formulate the most effective defense strategy. However, this privilege has certain exceptions, such as when the client intends to commit a future crime or fraud.