Cost-effectiveness analyses have shown that the cost per year of life saved by screening with any of the tests recommended is reasonable by US standards. Although the specific results vary among analyses, in general the marginal cost-effectiveness of this screening is less than $25,000 per year of life saved. Screening for CRC was among the highest ranked services in an analysis of the value of preventive services based on the burden of disease prevented and cost-effectiveness. Although the up-front costs vary by screening modality, the long-term cost-effectiveness is similar across screening tests, so that decisions about which options to include--in the long run and from the perspective of society--do not need to be affected heavily by costs. Costs increase out of proportion to benefits with shorter intervals between screening examinations. Screening has provided great opportunities. Screening can prevent CRC by polypectomy and find early-stage cancers for treatment with less morbidity. Screening can reduce the burden of treating advanced cancers and can identify families at increased risk. Screening also has provided a better understanding of the biology of CRC. Screening for CRC should be part of a complete prevention program that includes a healthy lifestyle and familial risk assessment. Individuals with increased familial risk require special screening approaches, whereas individuals with average risk can have more standard screening. The average-risk individuals can be stratified further into persons who require intensive follow-up and persons who require less intensive or no follow-up at all. We are beginning to learn how to apply screening and surveillance approaches based on risk stratification for a more cost-effective approach to conserve resources and reduce complications and costs. Chemoprevention can be added to the program when substantial benefit of agents has been demonstrated. We have a better understanding of the biology of CRC and the technology to intervene in that biology to make a difference in the lives of many people. We have the concepts and technology to reduce substantially the mortality for CRC and even prevent it entirely. Newer screening tests or others yet to be developed may, with time, replace the modern options. Screening should take place with the tests currently available and not wait until something better comes along. In this way, needless suffering and loss of life can be avoided for this leading cause of cancer death. Screening may become even more successful if the promise of new technologies is confirmed and they enter clinical practice. In the last analysis, the best test is the one that gets done and gets done immediately.