Inclusion Criteria:  For PrEP users (qualitative data, pilot, RCT):  Age ≥16 to 24 years* Female Have been on PrEP for a minimum of three months Good adherence to PrEP (i.e., self-report take PrEP all the time) Willing to disclose PrEP use to their peers Able to identify up to 4 peers at risk of HIV infection Willing to participate in 1-on-1 training by a study counselor on PrEP referral and HIVST use Willing to refer peers to PrEP and deliver HIVSTs Good communication skills, determined by the study counselor Able and willing to provide written informed consent Per the discretion of the site investigator, no clear risks of social harm or inability otherwise to reasonably conduct HIVST at home in the context of PrEP delivery  For peers of PrEP users (pilot, RCT):  Age ≥16 to 24 years* Female Referred by peer (i.e., a PrEP users) to initiate PrEP Able and willing to provide written informed consent  Per the discretion of the site investigator, no clear risks of social harm or inability otherwise to reasonably conduct HIVST at home  NOTE: We will only enroll young women ≥16 to 17 years into the study if they are emancipated minors and thus able to legally provide consent for participation in research. Kenyan law acknowledges women ages 14 to 17 who have become pregnant as emancipated minors. The PHRD site/UW collaboration has successfully enrolled emancipated minors into a number of prior studies, including PrEP clinical trials. In addition, Kenya national policy guidelines explicitly permit PrEP use in this age group.  Exclusion Criteria:  For PrEP users (qualitative data, pilot, RCT):  Age >16 or >24 years Male Have not used PrEP for a minimum of three months Poor PrEP adherence (i.e., self-reported) Not willing to disclose PrEP use to their peers Not able to identify up to 4 peers at risk of HIV infection Not willing to participate in 1-on-1 training by a study counselor on PrEP referral and HIVST use Not willing to refer peers to PrEP and deliver HIVSTs Poor communication skills, determined by the study counselor Not able and willing to provide written informed consent  For peers of PrEP users (pilot, RCT):  Age <16 or >24 years Male Not referred by peer (i.e., a PrEP users) to initiate PrEP Not able and willing to provide written informed consent