Implementation science and the HIV response: a critical juncture

Implementation science has grown quickly and been embraced by the HIV community. As our recent commentary highlights, current funding cuts are disproportionately hitting HIV in the implementation science – over 60% of the canceled implementation science was related to HIV. In addition, many of the programs delivering HIV prevention and treatment in the US and globally have been rapidly cut. Implementation science depends on implementation.

Critical juncture theory, drawn from political science and historical institutionalism, describes moments of significant change when established paths become unstable and new trajectories can be formed. These periods are typically triggered by crisis or external shocks, which describe the attacks on the institutions of health such as the CDC, NIH and USAID well. What follows is a branch point: at moments of institutional destabilization, the decisions that agents make (or do not make) during these periods shape the field for years or even decades to come.

Implementation science in the HIV response is in such a moment now. While grief about the wonton destruction of decades of progress is real, it might also be a moment to think about how new paths might be possible in this moemnt.

1. Advance mechanisms and generalizing.

Implementation science has been successful at naming strategies and fitting them into frameworks. To ensure that the science that remains is optimally impactful, we need a shift toward mechanisms. This means drawing not just from behavioral theory or quality improvement but from systems engineering, cognitive science, and critical social theory. By focusing on how and why strategies work across different systems, implementation research can be more generalizable and informative.

2. Evolve from add-on projects to core practice and program function.

Implementation is often used to study to health systems instead of embedded in them. A more transformative view sees implementation capacity as a function of systems. Along with other improvement sciences, implementation research can become a part of how systems are designed to learn, adapt, and make decisions. This would reposition implementation science as a foundational part of health systems, like data infrastructure or logistics. In HIV programs could become adaptive, with district managers, frontline workers, and communities use research principles to continuously redesign delivery in response to real-world change (e.g., migration, political instability, or drug shortages).

3. Deepen interdisciplinarity.

While the field desires interdisciplinarity, it draws relatively heavily from health services research and behavioral science. There is an opportunity to implementation science to lean into ideas from anthropology, political economy, systems theory, and design. Interdisciplinary practice could help reimagine how HIV care interfaces with housing systems, legal environments, or labor markets, especially in rapidly changing urban settings or among mobile populations.

4. From academic output to public relevance.

Finally, the field needs to rebalance what it rewards. Technical proficiency and rigorous study designs are important, but so is relevance. That means more public scholarship, community authorship, and policy-engaged research. Implementation science should help shape not only how evidence is used, but also its impacts and benefits. This could also mean developing indicators of relevance and legitimacy, not just effectiveness.

Even though this critical juncture is one that no one working in HIV wanted, we might be able to find more than risk there.