The firm's probate practice involves submitting wills to the court for probate or assisting the decedent's family with alternative heirship proceedings when the decedent died without a will. Once the will is probated, or heirs are determined, GSRP attorneys assist the family with administrative matters such as gathering, inventorying, and valuing assets in the estate, and preparing federal estate tax returns, state death tax returns, and state and federal gift or generation-skipping transfer tax returns. For clients who have just lost a loved one, estate administration can be a daunting task. The attorneys at GSRP provide thoughtful, competent assistance in meeting court filing deadlines and federal and state tax filing deadlines. The firm's estate administration practice involves advising executors and administrators on the legal and practical aspects of the administration of decedents’ estates. GSRP attorneys also represent beneficiaries of estates in negotiating settlements of estates, protecting beneficiaries' rights with regard to monitoring costs of administration, and advising in contested matters.

The firm’s domestic trust administration practice involves advising trustees on the legal, tax, and practical aspects of the administration of trusts. Conversely, GSRP attorneys also represent trust beneficiaries with respect to their rights as beneficiaries and the tax and non-tax aspects related to distributions from trusts.