Aggrey is an Environmental Health practitioner with over 11 years’ experience leading and collaborating in research studies across various themes including environment, mental health, resilience, sanitation and food security and nutrition. He is an environmental and social impact assessment expert and completed a Monitoring and Evaluation Fellowship from the University of Nairobi Institute of Tropical and Infectious Diseases (UNITID). He has expertise in statistics, panel studies and assessing impacts of interventions over time. He has authored/co-authored conference abstracts and manuscripts in peer-reviewed journals. His present research interests include child and adolescent mental health, water-based epidemiology and data science.