This literature review summarizes recent empirical research on obstacles preventing problem gamblers from seeking treatment for their gambling problems. Relevant databases and bibliographies were searched for English-language papers and reports published since 1998. The only methodological requirement was that gamblers themselves be asked about reasons for not seeking help. Nineteen studies conducted in five countries were identified. All except one targeted adults. Despite differences in methodology, many of the same barriers to treatment were identified. Most commonly reported barriers were: wish to handle problem by oneself; shame/embarrassment/stigma; unwillingness to admit problem; and issues with treatment itself. The authors of the review argue that unwillingness to admit to the problem may be even more prevalent than is typically indicated by the results of barriers studies. Other frequently reported barriers included lack of knowledge about treatment options and practical issues around attending treatment. More research is needed on barriers to treatment-seeking experienced by subgroups of gamblers defined by culture, ethnicity, gender, age. Open-ended questioning methods can help provide insights into what barrier categories mean to different groups and individuals. Input directly from gamblers can be combined with information from other kinds of studies to devise better ways of reaching problem gamblers, especially those in underserviced populations.