Actinic keratosis is responsible for more than eight million visits to dermatologists and primary care physicians annually. Actinic keratosis, the result of chronic sun damage to the skin, is closely linked to nonmelanoma skin cancer, both histologically and pathophysiologically. Clinical evidence shows that not only does actinic keratosis have the potential to progress and transform into nonmelanoma skin cancer, but it also may in fact be an early stage of cancer. The treatment of actinic keratosis is evolving from a "treat-as-you-go" strategy to a more preventive approach to curtail the potential emergence of nonmelanoma skin cancer. As the interrelationship between actinic keratosis and nonmelanoma skin cancer, squamous cell carcinoma, and basal cell carcinoma continues to strengthen, treating actinic keratosis as part of a preventive strategy to reduce nonmelanoma skin cancer is coming to the forefront. The following review of the relationship between actinic keratosis and nonmelanoma skin cancer discusses the rationale for early actinic keratosis treatment to prevent or reduce nonmelanoma skin cancer occurrence.