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Researchers generally use nonprobability methods such as chain-referral sampling to study populations for which no sampling frame exists. Respondent-driven sampling is a new form of chain-referral sampling that was designed to reduce several sources of bias associated with this method, including those from the choice of initial participants, volunteerism, and masking. This study expands this method by introducing “steering incentives,” supplemental rewards for referral of members of a specific group, injection drug users (IDUs) aged 18–25. The results are based on an interrupted time series analysis in which 196 IDUs from Meriden, CT, were interviewed before introduction of the steering incentives, and another 190 were interviewed afterwards. The steering incentives increased the percentage of younger IDUs sampled by 70%. We compared recruitment patterns with institutional data and self-reported personal networks to determine representativeness and whether volunteerism or masking were present. The results indicated that steering incentives helped to increase recruitment of younger IDUs, that the sample was representative, and that both volunteerism and masking were modest.