This article is a synopsis of paper SPE 54718, "Formation Damage Associated With Water-Based Drilling Fluids and Emulsified Acid Study," by J.D. Lynn, SPE, and H.A. Nasr-El-Din, SPE, Saudi Aramco, originally presented at the 1999 SPE European Formation Damage Conference, The Hague, The Netherlands, 31 May-1 June.