In this article, the authors describe the evolution of Oregon’s one-off property tax system, which emphasizes stable growth in tax assessments and payments and interjurisdictional uniformity in tax rates.They also compare two sections of Portland — the affluent neighborhoods on the west side of the Willamette River and the poorer ones on the east side — to determine how assessment quality and interjurisdictional tax burdens deteriorate without periodic reassessment.