Results are reported from a large (n = 3,402) four-group randomized trial to increase fruit and vegetable consumption among callers to the National Cancer Institute's (NCI's) Cancer Information Service (CIS) using tailored print materials. Following a baseline telephone interview, which included a brief educational message (BEM), participants were assigned randomly within CIS offices to one of four groups: single untailored (SU) group-one untailored set of materials; single tailored (ST) group-one tailored booklet; multiple tailored (MT) group-four tailored materials; and multiple retailored (MRT) group-four tailored materials with retailoring based on new information obtained at 5 months follow-up. Follow-up telephone interviews were conducted at 5 (n = 2,233) and 12 months (n = 1,927) after baseline. The main outcome measure was self-reported fruit and vegetable consumption using a seven-item food frequency questionnaire. At 12 months follow-up, there was a significant linear trend across groups of 0.21 servings (p = 0.0002). Specific nested hypotheses then were tested and revealed significant mean serving differences between SU (5.07) vs. MT (5.64) (p = 0.002) and SU vs. MRT (5.71; p