MTN-017 compared the safety and acceptability of daily oral emtricitabine/tenofovir disoproxil fumarate, daily reduced-glycerin 1% tenofovir gel applied rectally, and the same gel applied before and after receptive anal intercourse. The Data Convergence Interview (DCI) and the Pharmacokinetic Data Convergence Interview (PK-DCI) were brief, collaborative interactions conducted with participants during adherence counseling sessions to improve accurate measurement of adherence to study product use. DCIs converged data from product return counts and participants’ responses to daily text messages. PK-DCIs, conducted 4 weeks later, converged results of the DCI with PK from the corresponding period. CIs were easily incorporated into adherence counseling sessions, increased the accuracy of adherence data, and provided valuable context to data on product use. Participants were readily engaged in the interviews but, if they felt confronted, provided more guarded responses. As such, how these CIs are conducted is critical to engage participants, even those with poor adherence, to openly discuss challenges with product use.