To study adherence to product use prior to a Phase I microbicide trial, we recruited young men who have sex with men (YMSM) with a history of unprotected receptive anal intercourse (RAI) and provided them with 40 rectal applicators containing a placebo gel to use prior to RAI during a 12-week period. Ninety-five YMSM completed the trial. Based on a Computer Assisted Self Interview, 83 participants had receptive anal intercourse (RAI) (Median 12 occasions) using gel on 82.4 % of occasions (SD 26.7; 0–100). Based on an interactive voice response system, 88 participants had RAI (Median 10 occasions) using gel on 87.9 % of occasions (SD 20.0; 20–100). By applicator counts the median gel use was 12. Participants showed high adherence to gel use. Those who did not use the product consistently (n = 40) adduced not having it with them (85 %), forgetting to use it (48 %), not wanting to use it (13 %), partner refusal (10 %) and gel messiness (10 %).