Most major medical organizations recommend routine screening for breast, cervical, and colorectal cancers. Screening can lead to early detection of these cancers, resulting in reduced mortality. Yet, not all people who should be screened are screened regularly or, in some cases, ever. This report presents results of systematic reviews of effectiveness, applicability, economic efficiency, barriers to implementation, and other harms or benefits of provider reminder/recall interventions to increase screening for breast, cervical, and colorectal cancers. These interventions involve using systems to inform healthcare providers when individual clients are due (reminder) or overdue (recall) for specific cancer screening tests. Evidence in this review of studies published from 1986 through 2004 indicates that reminder/recall systems can effectively increase screening with mammography, Pap, fecal occult blood tests, and flexible sigmoidoscopy. Additional research is needed to determine if provider reminder/recall systems are effective in increasing colorectal cancer screening by colonoscopy. Specific areas for further research are also suggested.