Friction ridges cover the feet and hands and are accepted as a legitimate means of establishing identity. However, in some cases these ridges are not visible or are smeared, making the use of flexion creases an attractive alternative for establishing identity. Flexion creases are used less frequently and thus, the author undertook a study to demonstrate for a court of law that flexion creases have persistence over time and are an effective means of identification. Inked footprint impressions were collected from 50 volunteers over a 12-year period. The total number of creases for each foot was noted and the foot morphology of the earliest set of footprints for each subject was traced. Subsequent footprints from each subject were compared to the initial set. Upon examination it was evident that the number of creases per foot varied between 0 and more than 90 and averaged 15 per foot. Footprints were persistent over time and unique in configuration, making flexion crease analysis an effective means of identification, particularly when friction ridge detail is absent. Figures, references