Definition
An assignment is the transfer of one party's rights and obligations under a contract to a different party. In residential real estate, it most often shows up when a buyer under a purchase contract passes that contract along to a different buyer, often in exchange for a fee. As a homeowner selling your house, you have every right to limit or outright prohibit assignment in your purchase agreement if it's important to you to know exactly who will actually show up at closing. Contracts containing language like "and/or assigns" after the buyer's name are a signal worth paying attention to during negotiations.
Example
When reviewing her purchase contract, Denise noticed the buyer's name was followed by "and/or assigns," meaning the person signing might not be the one who ultimately closes on her home. Concerned about who would actually show up at the closing table, she asked her agent to explain what that language meant for her sale. Her agent recommended requiring proof of funds from whoever actually intended to complete the purchase before she accepted the offer, along with an earnest money deposit large enough to discourage a walkaway. Denise added those requirements as conditions to signing the contract. Denise added that requirement, and the original buyer ended up closing on the home himself without assigning the contract to anyone else. She said having that clarity in writing gave her much more peace of mind through the process.