A pseudo-operational trial using realistically handled articles was conducted at the Centre for Applied Science and Technology (CAST) to investigate fingerprint development approaches for treating flexible plastic packaging films. Vacuum metal deposition (VMD), superglue fuming followed by basic yellow 40 dye (SG/BY40), and powder suspensions were compared as primary chemical treatments. In contrast to the results of a similar trial carried out in 1986, we found that the effectiveness of VMD has diminished relative to that of SG/BY40. This is thought to be due to changes in the chemistry of the plastic material. Furthermore, the use of iron- or titanium-based powder suspension (a more modern fingerprint development process) was equivalent in effectiveness to SG/BY40. The application of different chemical and physical techniques in sequence to maximize the number of fingerprints developed was also investigated, resulting in a number of effective options including one for articles known to have been wetted. (Published Abstract)