Bites and stings from arthropods are largely inevitable because of the number of offending species and their distribution throughout our environment. Wasps, bees, ants, mosquitoes, gnats, chiggers, and fleas are found all across the United States. Thus far, Africanized honeybees are limited to southwestern states and fire ants to southern states. Brown recluse spiders are found most often in the Midwest and south central region, but the black widow spider is found in all 48 contiguous states. The dangerous Centruroides species of scorpion live mostly in southern states and California. Fortunately, in most people, bites and stings from arthropods produce only self-limited reactions, which can usually be managed with cold packs, analgesics, and topical agents. In the few encounters that produce serious reactions, prompt diagnosis and appropriate treatment result in a good outcome in nearly all cases. The number of stings and bites can be reduced with use of a few basic avoidance and protection measures.