Abstract: This study aimed at determining the influence of school principals' communication skills on the adoption and development of green technologies in public secondary schools in Kiambu County, Kenya. The research questions addressed was how do principal’s communication skills influence the development and adoption of green technologies in secondary schools in Kiambu County, Kenya? Grounded in Transformational Leadership Theory, the study used a mixed-methods approach with a convergent parallel design, combining cross-sectional survey and phenomenology. The target population was 292 public secondary schools, 292 principals, 6074 teachers, and 359,860 students, 16 sub-county directors and one county director from the Ministry of Education in Kiambu County. A sample of 167 principals, 181 teachers, 192 students, and 17 directors was selected using stratified random and multistage sampling. Data were collected via questionnaires, interviews, and focus group discussions. SPSS software version 2023 was used for quantitative data analysis, while qualitative data were analysed through content analysis. The study findings revealed that green technology adoption is limited, with water harvesting and energy-efficient jikos being the most common. Principals demonstrated moderate communication skills. Results further showed a significant and positive (β2=0.444, p=0.000) influence of principals' communication on green technology development and adoption secondary schools in Kiambu County, Kenya. The study further concludes that principal’s communication has a positive and significant influence on the the development and adoption of green technologies in public secondary schools in Kiambu County, Kenya. Recommendations includes communication training, regular updates and feedback mechanisms develop comprehensive communication plans, monitor and evaluate communication efforts and utilize diverse communication channels to enhance principal communication skill on green technologies. 

Key words: Communication Skills, Development, Adoption, Green Technologies, Schools