With the recent rise in biofuel processing plants materials selections need to be done for many new plant designs. Organic acids are one of the corrosion-causing byproducts along with aqueous carbonic acids chlorides etc. (depending on the feedstocks). Since no direct past experience with some unit designs was available especially for streams with high organic acid contents it was necessary to extrapolate from literature data and past somewhat similar operating experience to select candidate materials and to set up future testing programs. The materials under review include austenitic and duplex stainless steels and nickel-based alloys. This paper summarizes reviews done to date and gives examples of the initial materials selection decisions for various types of biofuels units.