Vapor corrosion is the acceleration of atmospheric corrosion of metals by trace amounts of volatile contaminants; typically these are volatile corrosive organic acids, especially formic and acetic acids. The main source of organic vapors is wood. The results of tests conducted on a variety of metals are presented in tabular form. Acetic acid vapors are more corrosive than formic acid vapors. This effect is particularly pronounced with magnesium, lead, zinc, and cadmium. Tin and nickel are slightly attacked at the highest concentrations of acetic acid, but this tends to be concentrated at discrete sites. Commercial low carbon sheet steel corrodes at a rate similar to iron; copper/zinc brasses corrode at a rate similar to copper. The corrosion of cadmium by propionic and butyric acids explains its susceptibility to corrosion by vapors from freshly applied drying oil paints. The corrosion of zinc by formaldehyde suggests that zinc presents a suitable catalytic surface for the oxidation of formaldehyde to formic acid. Tests were conducted on some anodic metal steel coatings. Zinc/nickel, manganese/selenium, and cadmium/tin showed a moderate resistance to corrosion by organic acid vapors.