This study investigated the influence that the "Environmental Leadership Professional Development" program had on preschool teachers. The program's aim is to enhance environmental awareness, thus developing environmental citizenship and leadership. The program offered experiential and reflective learning, meetings with environmental researchers and educators, discussions, a course website, and most uniquely, an environmental venture exemplifying active environmental leadership and citizenship conducted by the learners and accompanied by intensive professional support. Data sources included questionnaires presented before, immediately after, and one year after the program, and the portfolios documenting the venture's processes and outcomes. The qualitative evidence attests to affirmative change among the participants, who demonstrated personal growth and empowerment as educators and leaders, even a year after the program ended. The results indicate that the "Environmental Leadership Professional Development" program may serve as a professional development model for empowering teachers to become both environmental leaders and environmental citizen role models.