A recent Horizons study conducted jointly with two Dominican NGO - Centro de Orientación e Investigación Integral (COIN) and Centro de Promoción e Solidaridad Humana (CEPROSH) - and the National Program for the Control of STDs and AIDS (DIGECITSS) assessed the impact of two environmental-structural models in reducing HIV-related risk among female sex workers in the Dominican Republic and compared their cost-effectiveness. The models, built on years of experience gained from sex worker peer education programs, drew from the strengths of both community solidarity and government policy initiatives and engaged community members in both program and policy development. The models, developed after extensive formative research and consultation with sex worker peer leaders, were implemented in 68 sex establishments in two Dominican cities. In Santo Domingo, the nation's capital, a community-based solidarity approach to 100 percent condom use was implemented, while in Puerto Plata, a smaller coastal city in the north where tourism is prevalent, solidarity was combined with government policy and regulation. Solidarity-building activities included workshops and meetings with sex workers, sex establishment owners and managers, and other employees, such as doormen and deejays, to strengthen collective commitment to HIV/STI prevention, particularly in supporting sex workers to use condoms with partners. These gatherings also focused on exploring issues of trust and intimacy in condom use negotiation between sex workers and regular paying and non-paying partners. To enhance a collective commitment to prevention, each sex establishment owner was encouraged to ensure that 100 percent condom use posters and other awareness-raising materials, as well as glass bowls filled with condoms, were in place within each establishment. Other cues to support condom use included deejay messages about safer sex, information booths at establishment entrances, and participatory theater with male clients. In Puerto Plata, the same model was used but included a government-sponsored policy that required condom use between sex workers and all clients. Owners were told that they, not the sex workers, were responsible for ensuring compliance with the policy and with program activities. For those not in compliance, government officials imposed a graduated series of warnings, fines, and other sanctions, including closure of the establishment. Researchers used a pre-/post-test evaluation design to assess the two, year-long programs conducted in 34 sex establishments in each city. Structured surveys and non-routine STI testing were conducted among a random, cross-sectional sample of approximately 200 female sex workers, age 18 years and older, from the study establishments. Women were recruited at government health clinics in each city and data were collected at baseline and at the end of the 12-month intervention period. In both cities, the median age of female sex workers who participated in the baseline was 25 years; the median number of years of schooling completed was seven. More than 75 percent were single, and nearly two-thirds had a regular partner. The median number of reported encounters with paying clients in the last week was two in Puerto Plata (range: 0-32) and one in Santo Domingo (range: 0-30). Government health inspectors accompanied by NGO staff visited sex establishments in both cities on a monthly basis to assess compliance with five key elements: the presence of 100 percent condom use posters, availability of at least 100 condoms on site, visibility and accessibility of condoms for clients and sex workers, attendance of all of the establishment's sex workers at monthly STI check-ups, and a lack of a positive STI diagnosis among sex workers based at the establishment. Participant observations were also conducted pre- and post-intervention among a random sample of 64 sex workers in each city, by male NGO staff members posing as clients. Following a strict research protocol, each NGO staffer selected a sex worker, talked with her at a table in the establishment, then asked if she would be willing to have sex without a condom, presenting up to four reasons, developed during formative research, why he did not want to use one.