All three white-powder suspensions were similarly successful in rendering almost all of the deposited prints visible. No difference was observed in the number of potentially identifiable prints obtained in samples aged between 2 and 8 days after application of the fingerprints and wetting of the sample, irrespective of the technique used. The variation in efficiency occurred in the amount of potentially identifiable prints that were developed. The TiO2 solution proved to be least effective when used on the black bin bags; it produced the greatest amount of background staining. Similarly, Wet Powder was least effective on the orange carrier bags; a large amount of staining occurred. Generally, the black cowling proved to be the most difficult substrate on which to obtain potentially identifiable prints. This was due to the amount of background staining produced by each technique. In general, Wetwop produced the least amount of background staining in all cases. Various types of substrates representative of common nonporous materials were examined, including black bin bags, orange carrier bags, clear sandwich bags, and black cowling (removable engine covers). Three donors each deposited a series of 10 fingerprints per process. Descriptions of materials and methods address sample preparation, sample aging, and the fingerprint development processes. 6 references, 3 tables, and 2 figures