In view of the current need to achieve universal health coverage among adolescents and young people (AYP), this PhD study aimed to contribute to the evidence of how to increase coverage of sexual and reproductive health (SRH) services among adolescents and young people aged 15-24 years in urban communities of countries with a high burden of HIV, with a focus on measuring implementation, reach and impact on coverage. This study formed part of the Yathu Yathu (“for us by us”) study, a cluster-randomized trial (CRT), conducted in two urban communities in Lusaka, Zambia. Data used was routinely collected monitoring data from an innovative incentivized prevention points card system which allowed real-time electronic data collection and a nested case control study exploring factors associated with not accessing SRH services by adolescent boys and young men (ABYM). It evaluated the impact of the co-designed intervention on coverage of SRH services among AYP compared to the standard of care services after 24 months of implementation. Overall, the intervention reached a high proportion of AYP who consented to participate in the study in the intervention arm compared to the control arm. Additionally, coverage of SRH services among AYP was significantly higher in the intervention arm compared to the control arm largely driven by uptake of HIV testing services. Other findings showed that the intervention could be adapted to COVID-19 and implemented with fidelity, and though resulting in limited access due to these adaptations, it did not impact uptake of HIV testing services. I also found that age, employment, level of education attained and knowing a friend who had accessed a service were associated with reach of the intervention among ABYM. This research adds to the evidence base that providing co-designed incentivized community-based sexual and reproductive health services can reach AYP, especially with HIV testing services. However, broader strategies are needed to increase uptake of other HIV prevention services and for young men who are aged 20-24 years or are employed.