Larvae of the lepidopteran species Ephestia cautella (Walker), Corcyra cephalonica (Stainton), and Plodia interpunctella (Hubner) clung to and climbed paper, glass, aluminum foil, cellophane, polyethylene (PE). fluorinated ethylenepropylene (FEP), ethylenetetrafluoroethylene (ETFE), polyester (PET), polyvinylchloride (PVC), and polypropylene (PP) at the greatest angle of incline (90°). Larvae of 8 coleopteran specices climbed only 1 material (paper) at 90°. Larvae of some species could not climb some materials at a 5° incline. The coleopteran larvae ranked generally from best to worst climbers were Anthrenus flavipes LeConte, Dermestes maculatus De Geer, Tribolium castaneum (Herbst), Oryzaephilus mercator (Fauvel), Cathartus quadricollis (Guerin-Meneville), Trogoderma variabile Ballion, Attagenus megatoma (F.), and Lasioderma serricorne (F.). The test materials ranked generally from easiest to most difficult to climb were paper, ETFE, PET, foil, cellophane, PE, FEP, glass, PVC, and PP. Three coleopteran species, O. mercator, C. quadricollis , and D. maculatus clung to all materials at 90°. The other larvae ranked generally from best to worst clingers, were T. variabile , T. castaneum, A. flavipes, A. megatoma , and L. serricorne . The test materials, ranked generally from easiest to most difficult to cling to, were paper, glass, PET, ETFE, PVC, cellophane, FEP, foil, PE, and PP.