Shoeprints and fingerprints placed in blood on non-porous substrates are usually treated with chemicals to achieve a better contrast of the blood traces against the substrate. The subject of this research was to explore the possibilities to improve visualization of blood traces, after they were detected with luminol, by exposing them to other chemicals, such as leucocrystal violet, acid yellow 7, and/or Hungarian Red. The results show that leuocrystal violet appears to be a less suitable chemical to enhance visibility of blood impressions on non-porous substrates. (Published Abstract)