Rekeying  a residence involves altering the locks so that existing keys will no longer operate them. This process is often done for security reasons, such as when moving into a new home or after losing keys. Instead of replacing the entire lock, which can be costly and time-consuming, a locksmith can re-key the existing locks by adjusting the internal mechanisms so that they will only respond to a new set of keys. This provides homeowners with peace of mind, knowing that old keys will no longer grant access to their property, while also saving them money compared to installing entirely new locks.