Based in Tulsa, Oklahoma, The Allison Firm, PLLC, represents clients nationwide, handling matters related to estate planning, estate administration and probate and estate litigation. In its Northeast Oklahoma practice, the firm serves Green Country clients in Tulsa, Sand Springs, Sapulpa, Bartlesville, Owasso, Jenks, Bixby, Broken Arrow, Claremore, Catoosa, Arcadia, Grove and Vinita, and other cities in Tulsa County, Rogers County, Creek County, Muskogee County, Wagoner County and Osage County.