The 2025 Gordon Research Conference on Chloroplast Biotechnology will present cutting-edge research in all areas relevant to engineering chloroplasts to either improve existing functions or introduce new functions. The meeting will bring together a growing community of scientists who study and combine fundamental studies on chloroplast biology with the development of novel transgenic tools and synthetic biology to engineer organellar genomes in plants and applications. Breakthrough results in plastid biology will be highlighted. Genetic transformation of plastids is now possible in many plants and algae, and consequently synthetic biology solutions based on expression of multiple genes under sophisticated control circuits are becoming a reality. The plastid genome is now a prime target for ambitious projects aimed at design and synthesis of novel genomes with enhanced traits. The availability of protein-only genome editing reagents based on transcription activator-like effectors is enabling base editing of chloroplast and mitochondrial genomes. Such novel DNA base editing methods for organellar genomes are a real breakthrough and will be discussed. Chloroplasts are key organelles in the energy biology of plants; strategies to improve carbon fixation by reengineering of the photosynthetic machinery and carbon concentrating mechanisms, as well as the design of novel metabolic pathways that harness photosynthetic electron transfer will be explored. Engineering of novel functions into chloroplasts to make use of their extensive metabolic and protein synthesis capabilities is also at an exciting juncture and will be discussed. The basic science underpinning these advances (including genome structure and replication, control of gene expression, protein synthesis and import, assembly of protein complexes, protein quality control and turnover, plastid metabolism, metabolite transport) will be covered especially where relevant to these biotechnological applications. This conference is designed to attract attendees from both academia and the biotechnology industry and is intended to catalyze discussion and collaboration between researchers in the public and private sectors.