A number of biochemical and molecular process have been elucidated for insects exposed to potentially-damaging low temperatures. Often, the theoretical protection conferred by a given cold survival mechanism is insufficient to account for systems with robust survival, prompting the hypothesis that other mechanisms for low temperature tolerance must exist in these insects. With the advent of cDNA microarrays, discovering these mechanisms is now possible with a high ratio of data obtained per unit of laboratory effort. Genes that are upregulated in response to rapid cold hardening, cold shock, and short-term acclimation were identified using Sarcophaga crassipalpis cDNA hybridized to 12K Drosophila two-spotted arays. Analysis of the data thus gleaned revealed many genes that are commonly upregulated from more than one low temperature treatment and genes that are uniquely expressed for each of the treatment regimes. When grouped by function, genes involved in cytoskeletal organization, cellular defense, detoxification, and signal transduction were upregulated by low temperature treatments, indicating a possible involvement of these pathways for cold tolerance or repair. Where possible, confirmation of upregulation was performed using Northern blot hybridization or cross-species Northern blot hybridization (with Drosphila ESTs) if the gene could not be cloned from Sarcophaga.