The 2015 Gordon Research Conference on Microbial Population Biology will be a highly interactive meeting, promoting interdisciplinary discussions. The Microbial Population GRC is the central forum for discussion on microbial evolution, ecology and behavior and for identifying new research directions. The biennial conference will feature a broad range of topics including astrobiology, experimental evolution, microbial community dynamics, industrial applications, synthetic biology and molecular genetics. Participants include current and future leaders from their fields. Junior scientists and graduate students will have opportunities to present their research in multiple poster sessions, which are lively and highly interactive. The conference features programmed discussion sessions in the mornings and early evenings, with opportunities for informal gatherings in the afternoons and evenings.