Escrow is an arrangement where an intermediary or third party receives something from someone (party A), for the purpose of transferring that something to someone else (party B). Normally, the relevant transfer will not be carried out by the Escrow Agent unless certain conditions are met. In a typical stock transaction, money is transferred from Party A to the Escrow Agent to be released to Party B if Party B also transfer the relevant stocks to Party A. In the cryptocurrency world, automated smart contracts are often used to determine whether certain conditions are met.