To review the trends in and principles of cancer screening and early detection. Journal articles, United States Preventive Services Task Force (USPSTF) publications, professional organization position statements, and evidence-based summaries. Cancer screening has contributed to decreasing the morbidity and mortality of cancer. Efforts to improve the selection of candidates for cancer screening, to understand the biological basis of carcinogenesis, and the development of new technologies for cancer screening will allow for improvements in cancer screening over time. Nurses are well-positioned to lead the implementation of cancer screening recommendations in the 21st century through their practice, research, educational efforts, and advocacy.