Self-custody means you personally control your cryptocurrency without relying on a third party like an exchange or bank. When you self-custody, you manage your own private keys — and thus your crypto assets. Hardware wallets like Ledger and Trezor are popular tools for self-custody. This provides maximum security but also maximum responsibility: if you lose your keys, there’s no recovery process. “Not your keys, not your coins” is the mantra for self-custody believers.