Today's biometric technology makes non-violent methods of gaining access, even by the most experienced safe hackers and code crackers, nearly impossible. Modern vaults and safes are also reinforced to the point that the amount of explosives needed to blow them open would likely create unwanted attention and run the risk of harming the building to the point of collapse. By their very nature, even the most impregnable vault or safe eventually needs to be able to be opened and closed by someone. To circumvent vault and safe security features, robbers often kidnap the bank manager, but that is not always a successful ideal as banks have often removed the manager's ability to open the vault.