This technical report presents the current state of knowledge and gap analyses on corrosion testing of metallic materials produced using additive manufacturing (AM) technologies in environments relevant to several industrial applications. The discussed materials were produced primarily via laser powder bed fusion (LPBF), directed energy deposition (DED), and specifically the wire arc additive manufacturing (WAAM) form of DED. Many variables may not be sufficiently detailed in the rapidly evolving state of the art at the time of publication for the assessment of the performance of AM products; some variables such as microstructure, post-build processing, surface condition, residual stress, physical defects, and selection of representative test specimens (size and/or geometry) for a finished product are addressed. This report contains approaches for corrosion and environmental cracking assessment of AM materials, including test details that are relevant to the AM processes for some specific cases. The technical report provides the foundation for the preparation of test standard(s) that apply to AM products.