A power of attorney allows one person, known as the agent or attorney in fact, to make financial decisions for another, known as the principal. Powers of attorney are durable when the agents' authority is not affected by the incapacity of their principals. A power of attorney can be limited to a particular need or transaction, or it can be very general in scope. Because of advances in modern medicine, it is far more likely that someone will be incapacitated for a long period rather than die right away. For example, if John is in a serious auto accident and is unable to leave a skilled nursing facility for weeks, Jane can still manage all of their property. She can also buy, sell, or re-finance property, if she needs to do so. Without the power of attorney, and even though Jane is married to John, she may not be able to convince third parties, such as bankers, title officers, or stock-brokers, that she can make use of all of their community property, or any of John's separate property.