Research protocols must have a reasonable balance of risks and anticipated benefits to be ethically and legally acceptable. This article explores three characteristics of research on reproductive genetic technologies that complicate the assessment of the risk-benefit ratio for such research. First, a number of different people may be affected by a research protocol, raising the question of who should be considered to be the subject of reproductive genetic research. Second, such research could involve a wide range of possible harms and benefits, making the evaluation and comparison of those harms and benefits a challenging task. Finally, the risk-benefit ratio for this type of research is difficult to estimate because such research can have unpredictable, long-term implications. The article aims to facilitate the assessment of risk-benefit ratios in research on reproductive genetic technologies by proposing and defending some guidelines for dealing with each of these complicating factors.