Choose a style, first. Some passport wallets are classic folios designed to fit into a suit pocket or a purse, while others hang around the neck under your shirt, where pickpockets and the like can’t get at them. Depending on where you’re going, one style may make more sense than the other. If you won’t be taking your passport out anywhere other than the airport, for example, a folio may be more convenient. But if you’ve got rugged road ahead of you, a lanyard might give you peace of mind.