Bailment is the delivery of property from one person (bailor) to another person (bailee) who holds the property for a specific period of time under an express or implied-in-fact contract. To be distinguished from a contract of sale or a gift of property, bailment only involves the transfer of possession and not of ownership. An example of a bailment is taking your car to a parking garage and leaving the car and the keys in the possession of the parking garage attendant.

Bailments may be of several types: a bailment may be gratuitous when the bailee receives no compensation (as when you borrow your friend's notebook computer to work on an open source online encyclopedia project because he believes in the open source movement and wants to help you out), or a bailment for hire for which the bailee is compensated as in the parking garage example above, another common example is the coatcheck person.

A constructive bailment is a legal obligation that is imposed upon someone who has possession of property to return that property to the rightful owner as when the bailment is involuntary (done without intent or by accident but without negligence). An involuntary bailee may be liable in conversion if they do not return the property on the request of the bailor.