Sexual problems rank among the top unmet needs of cancer survivors. Over 60% (9 million) in the US end up with persistent sexual problems. Half report distress, yet fewer than 20% get professional help. Will2Love offers online help, encouraging partners to work together and singles to date again. Will2Love.com provides news, blogs, webinars, moderated online forums, and resources. It links to responsively designed intervention sites for men and women, offered as self-help subscriptions or in a package with telehealth counseling. The interventions each give information on sexual and fertility side effects across cancer sites, self-help strategies to prevent or overcome specific sexual problems, training in sexual and couple communication skills, advice on finding expert help, video interviews with real patients, and vignettes with actors. Sites were developed with 3 fast-track SBIR/STTR grants from NCI. Published and recently completed trials show their efficacy. A randomized trial (RT) of 186 couples after prostate cancer compared the same sex therapy intervention delivered online or in 3 in-person sessions, with a waitlist control (Schover et al. 2012, Cancer). Both formats significantly improved sexual function/satisfaction in men and partners, with gains maintained at 1-year follow-up. An RT compared our next version to urology care alone in a cancer center’s sexual medicine clinic. Treatment satisfaction improved for all men, but access to the web site did not enhance outcomes, with poor adherence. We revised the site extensively, adding goal-setting and tracking and improving navigation. In a pragmatic trial of 29 men (mean age 61±9, mean time since diagnosis 37 mos.±42) 86% accessed the site vs. 60% in the RT, with 59% viewing it for more than 30 min. compared to 34% in the RT. Mean time on site increased from 101±81 min. in the RT to 151±250 in the pragmatic trial, with 41% vs. 17% sharing it with a partner. Efficacy data is not yet available but 60% rated the site as helpful in understanding cancer’s impact on sex and 34% used it to make decisions about care or felt it improved their sex life. Phone coaching was optional, but 86% rated it very helpful. An RT of our female intervention randomized 58 women to web site alone or supplemented with 3 counseling sessions (Schover et al. 2013, JNCCN). Survivors of breast or gynecologic cancer completed questionnaires at baseline, posttreatment, and 6-month follow-up. Both groups improved significantly in sexual function/satisfaction, distress, and quality of life, but the counseled group initially had bigger gains on sexual function. Site usage was similar in the 2 groups (149±157 min.), but the counseled group’s usage was mainly during the treatment period. The self-help group continued using it during follow-up. By 6 months, groups’ improvement had equalized. We used this site in a multi-component intervention to prevent sexual problems in women starting aromatase inhibitors for localized breast cancer. Data analysis is ongoing, but at 12 months, only 15% of women gave up partner sex compared to 24% in our survey of a similar, untreated cohort. Scores on sexual function and distress also were far better than in the historical cohort. We will continue outcome studies as we go live with the commercial sites.