What is the difference between a trustee and a successor trustee of an irrevocable trust?

The trustee is the person who presently has the authority to carry on the business of the trust. If the trustee dies, resigns or is for some reason unable to continue their duties then a successor trustee is appointed. A well drafted trust will name a successor trustee and a process by which successor trustees may be appointed. If the trust instrument fails to provide for the appointment of a successor trustee then a court of equity can be petitioned to make an appointment. Once appointed, the successor trustee has all the powers and duties of the original trustee.