According to the American Bar Association Commission on Law and Aging, guardianship and conservatorship involve the following:

“Guardianship or Conservatorship is the legal tool of last resort for decision-making and management of your affairs. Generally a guardianship involves the court appointment of someone to act as guardian to manage the property and/or personal affairs of an incapacitated person (commonly referred to as the ward). Conservatorship typically involves management of just one’s assets without control over the person.”

Definitions vary from state to state, and to simplify we will just use only talk about guardianship even though it may cover the same concept as conservatorship in some states.

A form of limited guardianship is recognized in most states. Under it, the court can limit the guardian’s authority and tailor it to the specific areas of incapacity of the ward. Limited guardianship offers a more finely tuned and less restrictive approach to guardianship, but some courts have been reluctant to use it.

If someone is appointed a guardian, but that incapacitated person already has an agent under a durable power of attorney or under a health care advance directive, the court will normally determine whether the agent’s authority shall continue.

The following is quoted from the ABA.

“When do individuals normally need a guardian?

When they can no longer manage their affairs because of serious incapacity, and
No other voluntary arrangements for decision making and management have been set up ahead of time, or if they have been set up, they are not working well, and
Serious harm will come to the individual if no legally authorized decision maker is appointed.
Guardianship is a major intrusion into one’s life and should be used only where there is a serious inability to make or understand the consequences of decisions. ”
“A decision to seek guardianship should never be based on stereotypical notions of old age, senility, mental illness, or handicaps. A person has a right to make foolish or risky decisions. These decisions by themselves do not mean that the person lacks capacity. A competent person chooses to run risks. An incompetent person runs risks not by choice, but by happenstance.”